BRPI0911680A2 - "pig" and method for applying surface prophylactic treatment - Google Patents

Abstract

The invention relates to methods for forming at least one metal oxide on one or more internal surfaces of open or partially closed fluid transport or processing systems. The method involves applying at least one metal compound to the inner surfaces to be treated using, for example, one or more movable applicators, commonly known as "pigs". then the at least one metal compound is converted to at least one metal oxide, such as by heating the surfaces. In some embodiments, the at least one metal oxide provides a protective metal oxide coating adhered to such surfaces. Embodiments of the present invention may be performed in situ on existing fluid processing or conveying systems.

Description

“PIG” AND METHOD FOR APPLYING PROPHYLATIC SURFACE TREATMENTS ”

Cross Reference to Related Orders

This application claims the benefit of priority under PCT Chapter I, Article 8, and 35 USC § 119 (e) of US Provisional Application No. 61/161, 635, entitled “Pig and Method for Applying Prophylactic Surface Treatments”, filed on March 19, 2009, which is incorporated herein by reference in its entirety. This application is a continuation in part and also claims priority privilege under PCT Chapter I, Article 8, and 35 USC § 365 (c) of US Provisional Application No. 12/100, 910, entitled “Pig and Method for Applying Prophylactic Surface Treatments ”, filed on April 10, 2008, which is incorporated herein by reference in its entirety. Order '910 is partly a continuation of International Order No. PCT / US07 / 81230, entitled “Method for Proving Prophylactic Surface Treatment for Fluid Processing Systems and Components Thereof” filed on October 12, 2007, which in turn claims the priority privilege of US Provisional Order No. 60 / 851,354, entitled “Method for Proving Prophylactic Surface Treatment for Fluid Processing Systems and Components Thereof” filed on October 12, 2006. Both international Order '230 and Provisional Order' 354 they are incorporated by reference in their totalities.

Field of the Invention

This invention relates to processes and equipment used to apply coatings to the internal passages of a fluid processing system, especially tubes.

Description of the Related Art

Metal tubes are often used in a variety of industrial processes. There is often a need to reduce damage to the internal surfaces of metal tubes in heat exchangers, process systems and similar equipment, due to erosion, corrosion, accumulation of debris, or a combination of the two. For this purpose, a protective layer is often the preferred solution.

There are many devices for the inner lining of a pipe. The methods included in the prior art include brushing, scraping, spraying and others. Brushing devices and methods on an inner tube liner are disclosed in U.S. Patent Nos .: 2,048,912, 2334294, 2470796, 2551722, 2792807, 2800875 and 3516385. These patents disclose suitable methods for coating tubes at their manufacturing points. The technologies described here are not practical for coating pipes that are already assembled into useful components, such as heat exchangers, industrial process plants, fluid transport assemblies, or other end-use pipe applications. There is a need for a method for coating tubes that are already assembled and “in the field”, either before their first use, or after a period of service has already occurred and that it is desirable to apply a coating to “old” tubes that have already been cleaned.

Surface coatings that already exist in the art for industrial process systems often fall short of providing erosion, corrosion, or protection from accumulation of debris for many processes, especially those involving high temperatures or highly corrosive materials or a combination of two. In particular, there is a need in the petrochemical industry for a surface coating that can be applied to an assembly process system with the least possible disruption to the industrial plant and with minimal downtime, and that results in a coating that is resistant to highly harmful conditions.

An additional limitation of the current technique in pipe coverings is the thickness of the final protective layer. Due to the large temperature variations present in many industrial processes, the inadequacy of the thermal expansion coefficient between the pipe material and the coating material generally results in cracking and splintering of the current coatings, especially for thicker coatings.

Metals, ceramic materials, glass and ‘cermets’ are used to build several functional items, which in turn are used to carry out industrial processes. Under certain operating conditions of these processes, the degradation of a component's surface can result from many causes. These can include the corrosive nature of the particular process conditions, thermal effects of the process or the environment, the contamination of various elements that become deposited on the surface or infiltrate the material, the deposits formed by the catalytic activity between the material of the components and the fluid process, the galvanic activity between the component material and the process fluid, concentration cell corrosion, crack corrosion, graphitic corrosion, and a combination of these degradation mechanisms with each other or with other mechanisms.

During operation, various industrial process systems are degraded in the working sections of the system that is attacked by various chemicals and conditions. This occurs in the oil industry, dyes, cosmetics industry, food industry, pharmaceutical industry, chemical industry and in closed systems such as refrigeration systems, heating and air conditioning systems, and many others. Other systems that are affected by surface degradation are furnaces, boilers, internal combustion engines, gas turbine engine systems, rockets, etc. In any continuous or intermittent process system, there is a risk of surface degradation due to the exposure of materials to certain chemicals and conditions. The surfaces exposed to the process can degrade due to the degrading material itself, erosion or corrosion, or the degradation can be in the form of deposits that accumulate in the material, affecting the performance of one or the other, for example, flow efficiency through a tube. Any type of degradation is usually referred to as "deposits". The typical solution for this type of deposits and the qualitative improvement of the material used to build the functional item, be it a tube, a heat exchanger, etc. For example, a tube can be constructed of a nickel alloy in stainless steel, instead of ordinary carbon steel, in an attempt to improve the durability of its internal and external surface and / or functionality. As another example, tanks used to store various chemical materials can experience deposits of materials or reactions on the inner surface of the tank, which can negatively affect the efficiency of the overall process. In another example, a heat exchanger can be made of a high nickel alloy to allow it to withstand high temperature operations (as in the case of a hydrocarbon fuel gas turbine system) while also reducing the amount of precipitates and deposits that may be occurring due to the caustic environment in which the heat exchanger is required to operate. In another example, an exhaust valve for use in an internal combustion engine can be made of a special alloy, in an effort to reduce the amount of carbon deposits that form on its surface; Carbon deposits are a known source of operational and emission problems for internal combustion engines.

Many industrial processes use materials to contain and transport various liquids, fluid pulps or vapors, and the materials can be degraded during use. These problems are known as "flow assurance" issues, which is the industry term for the growth of flow restrictions in various pipes, tubes, heat exchangers, and process containers, etc. For example, the inside of a pipe used in an industrial process may have its effective cross-sectional area reduced during the operation of chemical deposits transported inside the pipe during various processes. In other cases, the vaporous or liquid elements carried inside a heat exchanger can precipitate the growth of crystalline deposits, if the favorable conditions (temperature, pressure, presence of catalyst elements, etc.) exist in the system. In an example of this problem, the crystals of various elements can grow during the fluid processing operation, because certain molecules exposed on the material surface of the interior of a conduit serve to catalyze the growth of some types of fibers on the interior wall of the conduit. For example, carbon fibers grow inside metal tubes used to transport ethylene, petrochemical cracking tubes, oil refinery heaters, natural gas turbine blades, propane and LPG transport tanks, etc. Although the mechanism of carbon fiber formation is not entirely clear, it is believed that exposed iron or other atoms on the surface of a steel or iron pipe, for example, in an oil processing facility, can play an important role in decomposition of hydrocarbons flowing in the carbon tube. Because carbon has some solubility in iron, a steel or iron tube can absorb that carbon. When the pipe material becomes saturated with carbon, amorphous carbon fibers begin to grow rapidly at process temperatures in the range of about 400 ° C to about 800 ° C. Such fibrous deposits and / or growths affect the development of the boundary layer of fluids and / or vapors that pass through the interior of the tube, and can induce a significant restriction on the tube's ability to transfer fluids, vapors or suspensions. In addition, a corrosive environment, especially due to the presence of water and impurities or salts dissolved in it, causes corrosion of the metallic tubes leading to failure. Furthermore, it is known that petrochemical process fluids that flow through a metal tube at a high temperature can cause the metal to wear out in what is known as metal sweeping, where the inner surface of the tube is corroded by various mechanisms. Consequently, there is a need in the art for a way to prevent or significantly inhibit the growth of carbon fibers, while inhibiting the chemical attack of corrosive elements on the substrate, such as those that result in the metallic sweeping of components within a system.

Throughout industrial operations, passageways and chambers regularly experience deposits on their internal surface caused by the precipitation of production fluids, deposits aggravated by high temperatures, solidification of matter in slow movement of the boundary layers, and deposits that occur by various other mechanisms. Some components, such as heat exchangers, can experience deposits from the processed fluid and the heat exchange medium, thereby experiencing the formation of deposits on multiple internal surfaces. In some cases, more than one internal surface contacts the hydrocarbons to be processed, such as in a heat exchanger that transfers heat from the processed material to the feed material. Other components, such as pipes, may corrode on external surfaces due to the process and / or environmental factors. The repair of such problems has high costs associated with it due to the interruption of production, while the sections of a process system are identified and then cleaned, diverted and / or replaced. The oil industry, for example, has literally thousands of kilometers of connective pipelines, tubes, collectors, as well as thousands of heat exchangers and process risers, etc., which require regular maintenance and repair at great costs for industry. For example, shutting down an oil refinery to repair and / or replace pipes with restricted flows results in losses of approximately $ 200,000 to $ 500,000 per lost production day.

In another example, at high process pressures and at temperatures above 0 ° C, methane gas, present in the petrochemical flow, can react with water to form ice structures called hydrates. The formation of hydrates in the flow lines of the production stream in the oil industry is also of great concern. The production flow lines carry the raw fluids produced from the wellhead to a processing facility. If a flow line is operated in the “hydrate formation region” (that is, under conditions in which hydrates can form in an oil or gas stream), hydrates can be deposited on the inner wall of the tube and accumulate until completely blocking the flow line and stop the transportation of hydrocarbons to the processing plant. Attempts to prevent hydrate formation involve injecting additives into the process fluid, but this can be an expensive solution.

Because the problem of deposits inside tubes and process tubes and the consequent reduction in flow is so great, there are a number of industry associations that participated in the study and improvement of flow guarantee in fluid processing systems. For example, the Gas Technology Institute estimates that the cost of repairing the damage that hydrate formation does to the industry is $ 100 million a year.

Deposits on the inner surface of a tube have a significant negative impact on the tube's ability to transfer liquids or gases, and these results may vary depending on the surface roughness of the tank. For example, a uniform deposit of 5% on the inside of a tube of circular section, can induce a loss of yield of 10%, and require a pressure increase of 30% to keep the flow constant. An irregular 5% deposit can increase the yield loss to 35% and require a 140% pressure increase to keep the flow steady. See introduction, Cordell to Pigging Pipeline, 5th Edition (ISBN0-901360-33-3).

The growth of deposits inside a tube can induce deposits or growths to become so large as to almost stop all flow of flow through the tube, as shown in Figure 2. Conditions like these can occur within a few months, or even within a few weeks of operation for certain industrial processes.

In other applications, scale is caused by precipitates formed within defined regions of a process system during oil and gas recovery, food processing, water treatment, or other industrial processes. The most common incrustations are inorganic salts such as barium sulfate, strontium sulfate and calcium carbonate. In some cases, the incrustations may be partly organic (naphthenates, MEG-based, etc.). Other scale formations may be composed of sodium chloride, iron carbonate and magnesium hydroxide. Inlays formed from sulfates are usually due to the mixture of chemically incompatible waters (such as seawater and formation water). Carbonate fouling results from the release of pressure from waters containing sodium bicarbonate at high concentration levels. The formation of incrustations degrades the efficiency of the process by obstructing the sand screens and the production pipeline, by causing failures in valves, pumps, heat exchangers, and separators. Fouling can also block pipelines.

In addition, the accumulation of combustion known as slag or encrustation usually forms on the surface heated by the flame of ovens, boilers, heating tubes, preheaters and reheaters. The degree of combustion accumulation depends on the quality of the fuel to be burned. Clean natural gas, for example, produces little or no accumulation, while coal, a “dirtier” fuel, generates significant combustion accumulation. In particular, coal-fired power plants experience accumulation of combustion in heating vessels in contact with coal combustion products. This decreases the accumulation of heat transfer across the surface to the substance to be heated and, therefore, energy losses. In addition, such an accumulation of combustion increases the temperature necessary to induce the substance to reach a desired temperature. This increased temperature creates stresses in the heating vessel, and can lead to material failure. Avoiding the accumulation of combustion on surfaces heated by flame from a fluid transport or the processing system can reduce energy consumption and extend the life of the equipment.

In some applications, surfaces exposed to the flow of liquids can become degraded by the nature of the fluid itself, for example, in the case of hydrogen transport and containment, which has the associated problem of weakening the exposed materials.

Across industry and technology, sensors detect the operating parameters of the various processes. By necessity, those sensors that inhabit the process material, are subject to these deposition mechanisms inherent in the processes they monitor. Unfortunately, even the smallest degree of fouling can affect the accuracy of a sensor, even if the same degree of fouling has only a negligible effect on the process itself. Often, the remedy for the deposit on the sensor is to design the sensor and the sensor mounting equipment for easy replacement of dirty sensors. The sensors represent high value components, and the frequent replacement of the sensor adds significant costs, in addition to loss of production due to the stoppage for the replacement of the sensor.

The hydrocarbon processing industry recognizes several different mechanisms for fixing process components due to the unique conditions of such processes. One mechanism, known as coking, results from the heating of hydrocarbons and extraction of the lighter boiling point fractions, causing thermal condensation of the heavier fractions. Asphaltenes, tar, inorganic material, and other solids will form on the surface of several petrochemical process units. In particular, vacuum columns, catalytic crackers, coconuts, viscosity breakers, and any equipment that handles heavier fractions of the oil at high temperatures suffer from coke build-up. In addition, the high temperature environment of an ethylene cracker causes the polymerization of the carbon-carbon double bonds, the product from which it condenses and forms a coke upon further heating. When high temperature plays a significant role and forms high molecular weight coke, the resulting material is called pyrolytic coke. In a different process, a kind of metal, such as iron or nickel catalyzes the dehydrogenation of a hydrocarbon, leading to what is known as catalytic coke. Elementary carbon then deposits in the metal, causing it to weaken. When the system is turned off and cooled for decoking or maintenance, the weakened metal can crack or chip. In some cases, carburized metal can produce chips at high process temperatures, resulting in the metal sweep mentioned above.

In addition to reducing the process transfer rate, the accumulation of coke decreases the heat transfer, requiring higher process temperatures, consuming more energy and decreasing the life of the equipment. Coke deposits can induce uneven heating, requiring lower temperatures to avoid safety problems. In addition, shutting down these systems to remove coke stops production. System stops and starts cause thermal stresses and increase the probability of system malfunctions and material failures. Reducing coke build-up can extend equipment life, improve process yield, reduce energy consumption and operating temperatures, increase safety, and produce cheaper alloys for equipment production. In addition, increasing the actual temperature of the process flow (not just the temperature outside the heated vessels) would increase process efficiency and throughput. In this way, many process temperatures are limited by the metallurgy of the heater tubes. The accumulation of coke requires that higher temperatures be applied outside to obtain a certain temperature inside the tubes.

A second distinct mechanism for the formation of deposits on equipment in the hydrocarbon industry is corrosion by one or more chemicals present in the process stream. In particular, hydrogen sulphide (H ₂ S) attacks metal surfaces, causing the formation of iron sulphates that decay from surfaces in contact with the hydrocarbon, reducing the thickness and strength of process equipment, obstructing passages, and reducing potentially the activity of downstream catalysts. The presence of ammonia (NH ₃ ), ammonium chloride (NH ₄ CI), or hydrogen (H and H ₂ ) stimulates the corrosive attack by H ₂ S. In addition, acids such as hydrochloric acid (HCI), naphthenic acids , sulfuric acid (H ₂ SO ₄ ) and hydrofluoric acid (HF) cause corrosive attacks at several points in hydrocarbon processing systems. For example, corrosion by naphthenic acids can be seen in process equipment that deal with diesel and heavier fractions, as naphthenic acids tend to have boiling points similar to diesel fractions. Corrosion by sulfuric acid and hydrofluoric acid occurs in the alkylation units and associated components that employ these acids. Protection against corrosive mechanisms can be found in the use of chromium, nickel and molybdenum alloys, and by adding substances to the process flow, such as bases to neutralize the acid. Ironically, H ₂ S is added to the process streams to reduce metal sweeping and other forms of deposition; yet H2S alone causes corrosion. This compound also appears during the hydrodesulfurization processes, when thiols and other organosulfur compounds naturally present react to form H ₂ S and desulfurized hydrocarbons. In addition, metallic systems that deal with alternative fuels such as alcohols including methanol and ethanol, have been shown to experience corrosion. Protecting equipment against corrosion mechanisms can reduce operating costs, increase the breadth of execution, extend equipment life, and produce cheaper materials available for equipment construction.

As oil resources become less abundant and more expensive, renewable sources of hydrocarbons are growing in importance. Biodiesel, for example, promises an alternative fuel to petroleum diesel, fuel derived from crude oil. However, biodiesel refining presents unique challenges to refining equipment. Normally, a strong base such as sodium hydroxide or potassium hydroxide in alcohol digests triglycerides and long-chain fatty acids from a biological or renewable source, to form esterified fatty acids (biodiesel) and glycerin. This source can be corn, soybeans, oil palm, cellulose, husk, restaurant waste and even garbage. The basic hostile environment required for the digestion reaction can induce caustic stress fracturing, also known as caustic embrittlement. Heat treatments and nickel-based alloys may be necessary to prevent cracking, unless a cheaper or more efficient means can be found to protect this equipment.

Surfaces contaminated with waste during the operation of the process often negatively affect the efficiency and / or functionality of the process itself. Currently, most cleaning methods for removing deposits on internal surfaces in systems of the types described above in process plants involve the use of one or more of the following strategies:

• chemical solvents such as kerosene or diesel oil, or strong aromatic solvents, such as xylene or toluene.

• Dispersants that act as surfactants • Exothermic chemical reactions • Mechanical cleaning methods such as scraping or blasting • Thermal cleaning methods involving heated oil or diesel, or the high-heat external application to break up surface deposits

These methods involve considerable time and effort on the part of the maintenance personnel of the industrial process unit, reducing production or transferring a system and producing the associated loss of revenue associated with the industrial unit.

Likewise, in metallic powder spraying operations, a chemical attack occurs inside the spray chamber that rapidly degrades its internal surfaces. In other applications such as food processing, beverage, and similar closed process systems, material degradation on the inner surface of many parts of a process system occurs due to chemical attack, material deposits, fibrous growth, and other surface contaminants .

Portions of fluid processing and transport systems exposed to the environment, especially those containing iron, also experience corrosion from environmental factors. The chemical, thermal and galvanic attack represent mechanisms that lead to incrustations of the external surface in these systems.

There is, therefore, a need for an improvement in the means of protecting surfaces in many functional components from a variety of contaminants that accumulate or chemical erosion that occurs, through various mechanisms, during the normal operation of the component. An improved treatment that can be applied and that provides proven resistance to surface contamination can serve to improve many processes currently in use in the industry. The invention disclosed here meets this need.

Description of the Invention

Several embodiments of the present invention are described here. These embodiments are only illustrations of the present invention. Numerous modifications and adaptations of the same will be easily perceived by those usually versed in the technique, without departing from the spirit and scope of the invention.

The invention described here provides methods for protecting surfaces of transport equipment or fluid process. As used herein, the term "processing or transportation system, or a component thereof" means any equipment within which the fluid (used here to include any material that is wholly or partially in a gaseous or liquid state, and includes without limitation, liquids, gases, two-phase systems, semi-solid systems, suspensions, etc.) flow or are stored, such as tubes, pipes, ducts, heat exchangers, beds, tanks, reactors, nozzles, cyclones, mufflers, chambers combustion, intake manifolds, exhaust manifolds, doors, etc., as well as any equipment within which a chemical or physical change occurs, in which at least one of the components participating in the chemical or physical change is a fluid. Methods of the invention protect the surfaces of the equipment by preventing degradation, regardless of whether the degradation occurs through the deposition of the material on the surfaces, through the infiltration of the material inside the surfaces, or through the corrosive attack on the surface of the material. The method is adapted to be used, in some modalities, in fluid process equipment, or parts of it, after assembly, resulting in significantly reduced interruption or interference with the protective functions of the coating by welds, joints, or other structures within the equipment that is created when the equipment is built or assembled.

The present invention relates, in some respects, to the formation of at least one metal oxide on an internal or external surface of transport equipment or fluid process. The at least one metal oxide can be formed on the surface by (1) placing at least one metal compound on the surface and (2) converting at least part of the metal compound into the form of at least one metal oxide. Metal compounds useful in the present invention contain at least one metal atom and at least one oxygen atom. Non-limiting examples of useful metal compounds include metal carboxylates, such as metal alkoxides and β-diketonate metals. The conversion of the metallic compound can be carried out by a wide variety of methods, such as, for example, heating the environment around the metallic complex, heating the substrate with the metallic compound, heating the metallic compound itself, or a combination of these three . In other embodiments, the conversion of the metallic compound can be carried out by catalysis.

Some embodiments of the present invention provide a method for forming at least one metal oxide on a surface of a fluid processing or transport system, or a part thereof, comprising: at least partially assembling the system; apply at least one metallic compound to the surface; and exposing the surface with at least one metallic compound applied to an environment that will convert at least part of the compound to at least one metallic oxide. In other embodiments, the fluid processing or transport system is substantially assembled to form at least one metal oxide coating on at least one surface of the system. In still other embodiments, the fluid transport or processing system is fully assembled before forming at least one metal oxide coating on at least one surface of the system.

In some embodiments, the invention relates to a method for forming at least one metal oxide on a surface of a fluid processing or transport system, or a part thereof, comprising: applying a metal compound composition to the surface, where the composition of the metallic compound comprises at least one metal salt of at least one carboxylic acid; and exposing the surface with the metallic composition applied to an environment that will convert at least part of the salt to at least one metal oxide.

In some embodiments, the invention relates to a method for forming at least one metal oxide on a surface of a fluid processing or transport system, or a part thereof, comprising: applying a metal compound composition to the surface, where the composition of the metallic compound comprises at least one metallic alkoxide, and expose the surface with the metallic composition applied to an environment that will convert at least part of the metallic alkoxide to at least one metallic oxide.

In some embodiments, the invention relates to a method for forming at least one metal oxide on a surface of a fluid processing or transport system, or a part thereof, comprising: applying a metal compound composition to the surface, where the composition of the metallic compound comprises at least one metallic β-diketonate; and exposing the surface with the metallic compound composition applied in an environment that will convert at least part of the metallic β-diketonate to at least one metallic oxide.

In further embodiments, the invention relates to a method for forming at least one metal oxide on a surface of a fluid processing or transport system, or a part thereof, comprising: applying a metal compound composition to the surface, where the composition of the metallic compound comprises at least one rare earth metal compound, and at least one transition metal compound; and exposing the surface with the metallic composition applied to an environment that will convert at least part of the compound to at least one metal oxide. In some embodiments of the methods of forming at least one metal oxide on a surface of a fluid processing or transport system, the at least one metal oxide comprises a metal oxide coating or metal oxide film. A metal oxide coating or metal oxide film, in some embodiments, is crystalline, nanocrystalline, amorphous, thin, or diffuse, or a combination of any of the above. For example, a metal oxide coating in some embodiments of the present invention can comprise a film that contains both the nanocrystalline and amorphous regions. In some embodiments, a metal oxide coating or metal oxide film, diffuses or at least partially penetrates the surfaces of the processing or fluid transport system, thus preventing any intermediate binding layers.

The invention, in additional embodiments, relates to a method for forming at least one metal oxide on a surface of a fluid processing or transport system, or a part thereof, comprising: applying a liquid metallic compound composition to the surface, where the liquid composition of the metallic compound comprises a solution of at least one rare earth metal compound and at least one transition metal compound, in a solvent, and expose the surface with the liquid compound applied to a heated environment that will convert at least some of the metal compound to at least one metal oxide, forming a metal oxide coating on the surface.

As provided herein, provided for herein, in some embodiments, the metal oxide layer may be crystalline, nanocrystalline, amorphous, thin-film, or diffuse, or a combination of any of those mentioned. For example, a metal oxide coating in some embodiments of the present invention can include a thin film that contains both the nanocrystalline and amorphous regions.

In other embodiments, the invention relates to a method for forming an oxidizing coating on an internal surface of a fluid processing or transport system, comprising: applying a liquid composition of metallic carboxylate to the surface, where the liquid composition of Metallic carboxylate comprises a solution of at least one rare earth metal salt of a carboxylic acid and at least one transition metal salt of a carboxylic acid, in a solvent, and expose the surface with the liquid metallic carboxylate composition applied to a heated environment that will convert at least part of the metallic carboxylate to metallic oxides, forming a thin layer of nanocrystalline coating on the surface.

In some embodiments, the invention relates to a method for forming an oxidizing coating on an internal surface of a fluid processing or transport system, comprising: applying a liquid composition of metallic carboxylate to the surface, where the liquid composition of Metallic carboxylate comprises a solution of zirconium carboxylate and at least one transition metal salt of a carboxylic acid, in a solvent, and exposes the surface with the liquid metallic carboxylate composition applied to a heated environment that will convert at least some of the metallic carboxylate for metal oxides, thus forming a thin layer of nanocrystalline coating on the surface.

In additional embodiments, the method of the invention also includes a step of applying a solution of organosiloxane-silica in ethanol over the formed oxide layer and exposing the coated substrate to an environment that will remove volatile components from the solution without decomposing the organo-bonds. silicon. In some embodiments, this step can be repeated one or more times.

The various coatings of the present invention are formed, in some embodiments, through a method of forming an oxidizing coating on a substrate consisting of:

(a) applying a liquid metallic compound composition to the substrate, where the liquid metallic compound composition comprises a solution of at least one rare earth metal compound and at least one transition metal compound, in a solvent, and (b ) expose the substrate with the liquid metallic compound composition applied to an environment that will convert at least part of the metallic compound to metallic oxides, forming an oxidizing coating on the substrate.

In other embodiments, the invention relates to metal oxide coatings (and articles thus coated), containing two or more rare earth metal oxides and at least one transition metal oxide. Other embodiments of the invention relate to metal oxide coatings (and articles thus coated), containing ceria, a second rare earth metal oxide, and a transition metal oxide. Some modalities refer to metal oxide coatings (and articles thus coated), containing yttria, zirconia, and a second rare earth metal oxide. In some cases, the second rare earth metal oxide may include platinum or other known catalytic elements.

In the case of catalytic surfaces, this method allows cost savings by reducing the mass quantity of the catalyst. In addition, it also allows a greater variety of catalysts to be applied either as mixtures or in individual layers to achieve better targeted results.

Therefore, some embodiments of the invention create a protective layer of metal oxide on a surface chosen to serve as a prophylaxis against chemical, thermal, ionic, or electronic degradation. Metal oxide coatings of some modalities prevent the growth of fibers, the formation of hydrate crystals, and act as a general prophylaxis against the growth of all materials that obstruct, interfere or contaminate the successful operation of a closed system.

Accordingly, some embodiments of the present invention provide a method for reducing or preventing scale build-up on the surface of a fluid processing or transport system, or part of it, including applying at least one metallic compound to the surface, and exposing the surface with o at least one metallic compound applied to an environment that will convert at least part of the compound to at least one metal oxide, where at least one metal oxide is resistant to fouling.

Other embodiments of the present invention provide a method for reducing or preventing scale on the surface of a sensor, or a component thereof, including applying at least one metallic compound to the surface, and exposing the surface with at least one metallic compound applied to a environment that will convert at least part of the compound to at least one metal oxide, where at least one metal oxide is resistant to fouling.

Some embodiments of the present invention provide a method to reduce or prevent the accumulation of coke on a surface of a fluid processing or transport system, or a part thereof, including applying at least one metallic compound to the surface, and exposing the surface with at least one metallic compound applied to an environment that will convert at least part of the compound to at least one metal oxide, where the at least one metal oxide is resistant to coke buildup.

Other embodiments of the present invention provide a method to reduce or prevent corrosive attack on a surface of a fluid processing or transport system, or a part thereof, including applying at least one metallic compound to the surface, and exposing the surface with o at least one metallic compound applied to an environment that will convert at least part of the compound to at least one metal oxide, where at least one metal oxide is resistant to corrosive attack.

Still other modalities provide methods to reduce or prevent combustion build-up on a flame-heated surface of a fluid processing or transport system, or a part thereof, comprising: applying at least one metallic compound to the surface, and exposing the surface with at least one metallic compound applied to an environment that will convert at least part of the compound to at least one metal oxide, where the at least one metal oxide is resistant to the accumulation of combustion.

Additional modalities provide methods to reduce or prevent the fouling of at least one metallic surface of a combustion engine system or a component thereof, comprising applying at least one metallic compound to the surface, and exposing the surface with at least one compound metal applied to an environment that will convert at least part of the compound to at least one metal oxide, where at least one metal oxide is resistant to fouling.

In some embodiments, at least one metal oxide is operable to render a surface of a processing or fluid transport system treated with it resistant to degradation or fouling for a period of at least days or weeks. In another embodiment, at least one metal oxide is operable to render a surface of a processing or fluid transport system so treated resistant to degradation or fouling for a period of at least months or years.

Some embodiments of the invention provide an improved surface treatment resistant to corrosion by creating a nanocrystalline granulation structure of zirconia-based materials or cerium-based materials, or surface treatments of other elemental nanocrystalline compositions with microstructures that serve to isolate the substrate chemical, thermal or galvanic attack.

Additional modalities provide a low cost means to form a useful coating of ceramic material based on zirconia-ceria on a substrate, the coating having a nanocrystalline microstructure.

Some modalities of the technology will prevent electrochemical corrosion by inhibiting the flow of electrons or ions into or from the surface of the substrate and from or into the stream of process fluid.

Additional embodiments of the invention produce a dense metal oxide coating that does not suffer from cracking due to thermal stresses.

Some modalities produce a metal oxide coating that does not suffer from cracking due to its manufacturing method.

In additional embodiments, at least one layer of metal oxide becomes uniform and without cracks or holes from a magnification of about 100x to about 1000x.

Some embodiments provide a metal oxide coating comprising only a metal oxide. Other embodiments provide a metal oxide coating comprising only two metal oxides. Still other modalities provide a metal oxide coating with only three metal oxides. In still other embodiments, the metal oxide coating is composed of four or more metal oxides.

The present invention, in some cases, also provides a low-cost method for creating a metal oxide coating that serves to protect a surface from chemical, thermal and / or galvanic attack. The present invention also provides a means to diffuse selected surfaces with selected chemical ingredients through a process that does not require the damaging cycles at high temperatures, in a variety of ways.

However, other embodiments of the present invention provide corrosion resistant coatings of organosiloxane-silica on the metal oxide coating to give prolonged utility to the substrates, when such substrates tend to corrode in aqueous environments, with or without the addition of salts and other impurities dissolved in water.

Additional embodiments of the invention provide a means to form a metal oxide coating within a closed system after it is assembled, providing a prophylactic cover on all surfaces exposed to the selected process, including welded areas, flanged joints, etc. Additional embodiments provide a fluid processing or transport system that comprises at least one surface comprising at least one metal oxide coating, the system having a large size.

Some embodiments of the invention can be implemented so that metal oxide coatings are formed on the components of a fluid processing system prior to assembly, for example, to a tube or heat exchanger at its original manufacturing site. In this way, mass coatings of metal oxides can be formed in a more automated way in these modalities, thus providing a coverage in most of the internal surface of a system while still providing a lower but selected level of protection against degradation of the system. that is, leaving the welded areas in the field uncovered, which may be suitable for some applications. In other embodiments, only certain surfaces within a system can be coated for the desired performance, sealing it for surface protection against degradation, catalytic activity, or a combination of these.

Therefore, additional embodiments of the present invention provide articles of manufacture adaptable to provide a surface of a fluid processing or transport system, or a part thereof, where the surface comprises at least one metal oxide. In some of these modalities, at least part of the metal oxide is present as a diffuse layer.

Some embodiments of this invention provide a process for applying a surface treatment to the inner surface of an industrial process system or a part of it such that erosion, corrosion, or the accumulation of debris or a combination thereof is satisfactorily resisted by the treatment. surface and underlying surface, resulting in better performance of the industrial fluid processing system or its components.

Other embodiments of the invention provide a method of forming a metal oxide coating that adheres well to the selected internal surfaces of the industrial process system.

Still other embodiments of the invention provide a method of forming a metal oxide coating within a closed piping system, where the coating has a thickness of 5 microns or less.

Additional embodiments of the invention provide an economical means to form a metal oxide coating on internal surfaces selected from an industrial process system.

Still other embodiments provide a method of forming an oxide coating of the metal on at least one component of an industrial process system prior to assembly.

Additional modalities provide a method of forming a metal oxide coating on at least one component of an industrial process system that has been in service, in which the component's internal surface, for example, a pipe or tube, has been cleaned with any method suitable for cleaning internal surfaces of components of the industrial process system, such as washing solvent, blasting, scraping, conditioning, mechanical and / or chemical polishing, shot blasting, steam cleaning, and similar methods.

Still further embodiments of the invention provide a method of forming a metal oxide coating on at least a portion of an industrial assembly process system, so that welded areas, flanges and various concentration points within the system receive the coating.

Other additional embodiments provide a method of forming a metal oxide coating on at least a portion of an industrial assembly process system, after all assembly welding, brazing, and similar joining processes are completed, when desired , to eliminate the degradation that occurs when components with pre-existing coatings are joined with joining processes at elevated temperatures. For example, the creation of a welded joint in a tube with a conventional surface treatment generally results in the degradation of the conventional surface treatment in areas bordering the welded area, reducing or eliminating the effectiveness of conventional surface treatment.

Other embodiments of the invention provide a method of forming multiple layers of at least one metal oxide in at least a portion of an industrial assembly process system.

Some embodiments of the present invention provide a method for forming at least one metal oxide on the inner surface of a fluid processing or transport system or component, comprising:

place at least one “pig” as close to the inner surface;

apply at least one metallic compound on the internal surface with at least one “pig”; and converting at least part of the metallic compound to at least one metallic oxide.

In other modalities, the process of placement, application and conversion can be repeated, forming at least one metal oxide in more than one layer. In yet other modalities, several methods can be used to apply at least one metallic compound to the internal surface, in addition to methods that employ at least one “pig”, again forming at least one metallic oxide in more than one layer. Thus, in certain embodiments, the present invention relates to processes for applying a chosen composition to the selected surfaces of an industrial process system, then using a conversion method to convert the formulation to a useful surface coating.

In some embodiments of methods of the present invention, at least a metal oxide or metal oxide coating is formed in an inert environment, including an environment where there is no oxygen, or substantially no oxygen is present. In other embodiments, at least a metal oxide or metal oxide coating is formed in an aerobic environment.

Industrial fluid processing and / or transport systems operable to be treated with metal oxides including metal oxide coatings, according to some embodiments of the invention, include without limitation oil refineries, petrochemical processing plants, transportation and storage facilities for petroleum such as pipelines, oil tanks, fuel transport vehicles and fuel tanks and pumps at filling stations, sensors, industrial manufacturing units and chemicals, storage and transport systems for aeronautical and aerospace fluids, food and dairy processing, combustion engines, turbine engines, and rocket engines.

Brief Description of Drawings

Additional aspects, characteristics and advantages of the present invention will become evident from the detailed description of the modalities presented below.

Figure 1, adapted from Figure 6 of US Patent. No. 5230842, shows a pig assembly useful in some embodiments of the present invention for depositing at least one metallic compound on the inner surface of a fluid processing or transport system.

Figure 2 shows a photograph of a cross section of an untreated tube revealing crystalline growth that restricts the flow through the tube.

Figure 3 shows a photograph of an uncoated steel coupon after an hour of exposure to Aqua Regia.

Figure 4 shows a photograph of a steel coupon coated with “Zircon” after an hour exposed to Aqua Regia.

Figure 5 shows a photograph of a steel coupon coated with “Glass”, after one hour exposed to Aqua Regia.

Figure 6 shows a photograph of a steel coupon coated with “YSZ” after an hour exposed to Aqua Regia.

Figure 7 shows a photograph of a steel coupon coated with “Clay”, after one hour exposed to Aqua Regia.

Figure 8 shows TEM micrographs in magnification of about two million x of a steel substrate with a Y / Zr oxide coating, in cross section.

Detailed Description

As used here, the term "rare earth metal" includes the metals in the periodic table lanthanide series, including lanthanum. The term "transition metal" includes metals from Groups 3-12 in the Periodic Table (but excludes rare earth metals). The term "metal oxide" particularly as used in conjunction with the above terms includes any oxide that forms or is prepared from metal, regardless of whether it is naturally occurring or not. The "metallic" atoms of the metal oxides of the present invention are not necessarily limited to the elements that readily form metallic phases in pure form. "Metallic Compounds" include substances such as molecules that comprise at least one metal atom and at least one oxygen atom. Metallic compounds can be converted to metal oxides upon exposure to a suitable environment for an appropriate amount of time.

When used in this document, “phase deposition” includes any coating process on a substrate that is followed by exposure of the substrate and / or the coating material, to an environment that causes a phase change, both in the coating material, in one or more components of the coating material, or of the substrate itself. The phase change can be a physical phase change, for example, a change from liquid to solid, or from one crystal phase to another, or from amorphous to crystalline or vice versa. “Adaptable to deliver” indicates the ability to deliver. For example, an "article adaptable to provide a processing or fluid transport system surface" is an article, such as a pipe, that has a surface that is or can be assembled in such a system using manufacturing steps, construction, and / or assembly.

In some embodiments of the invention, a device known as a "pig" is used. A “pig” comprises any suitable features and characteristics. A “pig” comprises a body and, optionally, one or more brushes, spray nozzles, absorbent structures, such as polymeric foams and sponges, stabilizers, hydraulic cups, hydraulic drive wheels and / or tracks, mechanically oriented wheels and / or tracks, conversion devices such as IR emitters, and so on. In some modalities, the “pig” can act to distribute at least one metallic compound on the surface to be treated. In other modalities, the “pig” works as a mobile plug, containing a volume of at least one metallic compound, in order to distribute it on the surface. In still other modalities, the “pig” works as a mobile converter, causing at least part of the metallic compound to convert to at least one metallic oxide.

In certain embodiments, a “pig” is or comprises a sponge. Suitable sponges include, but are not limited to, open cell foams, closed cell foams, sponges larger than the inner diameter of a pipe to be treated, and sponges comprising polyurethane, polyester, polyethylene, polyvinyl alcohol, cellulose, sponge natural and combinations of those mentioned. It is customary to use “pigs” that are reasonably dense and relatively incompressible, and that have a diameter that is perhaps five percent larger than the inside diameter of a tube to be treated with the “pig”. However, if that “pig” is damaged during its passage through the pipe, the “pig” may lose its ability to form a sufficient seal to allow the “pig” to be pushed through the pipe. Applicants have unexpectedly discovered that the use of a highly compressible sponge such as "pig" provides numerous advantages over less compressible "pigs". Some of these advantages, one or more of which need to be present in a given embodiment of the present invention, include:

• highly compressible sponges are better able to maneuver with “mule ears”, which are 90-degree inserts from one tube into another, and other difficult tube geometries such as elbows and U-curves. In some cases, a compressible sponge can navigate a U-curve that appears very close to the launching flange of the “pig”, whereas a rigid “pig” cannot build the momentum necessary to overcome the U-curve. Rigid pigs often get stuck and destroy themselves when navigating difficult pipe geometries.

• highly compressible sponges can treat tubes with different internal diameters. A less compressible pig moving from a smaller diameter to a larger diameter can lose its ability to form a seal, and can become trapped in the widest portion of the pipe. A highly compressible sponge having substantial "deflection" or resilience, can expand to fully contact the entire inner surface of the widest part of the tube, and is less likely to lose its sealing ability.

• A highly compressible sponge, such as an open cell foam sponge, can absorb a treatment liquid, and then apply the liquid to the inside surface of a pipe. On the other hand, a non-compressible “pig” requires that a quantity of the treatment liquid be placed in the tube before the “pig”. This can cause confusion, or it may require another "pig" to contain the treatment liquid.

• A sponge does not need to have a particular shape, whereas a “pig” is usually manufactured in a certain way so that it can travel through a tube. This advantage allows cost savings, in addition to the greater maneuverability as mentioned above.

In additional embodiments, a scraping package comprises a first "pig" and a second "pig", and an amount of coating liquid comprising at least one metallic compound. Other modalities include one or more additional "pigs" or other components positioned between the first "pig" and the second "pig". In some embodiments, the first “pig” acts as a sealing element within a pipe or tube and a second “pig” is positioned within a chosen section of a tube at a distance behind the first “pig” in such a way that a volume is defined by the rear section of the first “pig”, the inner walls of the tube, and the front segment of the second “pig”. This defined volume can be filled with the coating liquid and the second “pig” is constructed so that as the pair of “pigs” is transported along the length of the tube, a thin film of the liquid is allowed to leak through the “pig” ”Companion (second) and in this way the liquid becomes distributed over the inner surface of the tube.

In some implementations of the invention the accompanying “pig” can be constructed with an external surface being composed of an absorbent material, for example, urethane foam, so that the accompanying “pig” (second) serves as a mop that applies the liquid on the inner surface of the inner walls of the tube. In this implementation of the invention the volume of liquid that resides between the first “pig” and the second “pig” serves as a reservoir to keep the accompanying “pig” saturated with the liquid formulation such that the wetting of the inner surface of the inner walls of the tube it is performed continuously over a selected length within the tube.

In some embodiments of the invention, the driving force for the movement of the scraping package can be provided by air or by another gas pressure supplied behind the accompanying pig, taking advantage of the fact that the resident coating liquid between the two “Pigs” is an incompressible liquid and thus the pressure of the gas acting on the accompanying “pig” (second) will be transferred to the first “pig” (leader) and, as long as the gas pressure beyond the “pig” Leader (first) is sufficiently less than the gas pressure pressing on the rear side of the accompanying “pig” (second), the movement will occur so that the scraping pack moves towards the lower gas pressure zone inside the tube. In some embodiments, the gas pressure that presses against the accompanying “pig” may need to be greater than the gas pressure in front of the leading “pig” by up to 4.14 MPa (600 psi) in some cases to promote moving the scraping pack. In other embodiments, gas pressure can be supplied using any suitable methods, such as, for example, one or more of the compressors, fans, pumps, chemical reactions, combustion and so on.

In other embodiments of the invention, the driving force for the scraping package can be provided with inert gas or compressed gas mixture such that the wet internal surfaces of the piping system are at least partially prevented from oxidation, once wet with the coating liquid . In some embodiments, the inert gas or gas mixture can be heated to a temperature chosen sufficient to convert at least part of the coating liquid that wets the inner surfaces of the tube into a metal oxide coating.

In other embodiments of the invention, an inert gas can be introduced into the piping system after it has been wetted with the liquid coating, but before heating a portion of the pipe walls. The inert gas, in some modalities, controls the oxidation of the surfaces of the wet tube as their temperature is increased.

In other embodiments of the invention, the driving force for the scraping package can be provided by hydraulic pressure supplied to the rear sections of the accompanying pig, said hydraulic pressure being sufficiently higher than the pressure, whether gas or hydraulic, that exists in front of the leading pig, and thus promoting the desired movement in the scraping package. In still other modalities, the frictional forces that exist between the “pigs” and the inner walls of the tube will determine the amount of pressure, whether gaseous or hydraulic, that will be needed to move the scraping package through the pipe at the desired speed.

In some embodiments of the invention, a spray head can be provided in one or both "pigs" through which the coating material can be applied to the inner surface of the tube. In some interactions of this modality, the pressure required to discharge the coating material can be provided by a pressure vessel provided in the scraping package, as taught in the US Patent. No. 4774905, which is incorporated by reference in its entirety.

In other embodiments, the pressure required to discharge the coating material can be provided by the driving pressure, whether hydraulic or gaseous, which can be used to push the scraping package through the piping system. In these modalities, the driving pressure that is acting on the accompanying “pig” will be physically transferred to the resident coating material between the two scraping elements, thereby pressurizing the liquid coating material within that defined reservoir. This pressure can be used to force the liquid coating material through one or more spray nozzles to apply the coating material to internal surfaces of the tube. In some embodiments where the motive pressure is higher than necessary for an efficient spraying of the liquid coating material, a known pressure regulator can be provided between the pressure coating material reservoir and the head (s) spray that limits the liquid supply pressure to the spray head to a desired level, for example, 689.5 kPa (100 psi).

In some embodiments, the liquid coating material may be supplied by a feed line connected to one of the scraping elements such that one or both scraping elements remain saturated with the liquid coating material and a desired amount of liquid is disperses the inner surface of the pipe. In this interaction, the feed line may have guide discs provided along its length to prevent the line from touching the inner surfaces of the tube and thereby restrict the movement of the line.

In other embodiments, the liquid coating material can be supplied by a feed line connected to one of the scraping elements such that at least one spray nozzle provided with the set of “pigs” can receive a sufficient amount of coating liquid to disperse a desired amount of liquid over the chosen surface of the tube.

In still other embodiments, the pressurized liquid coating material can be supplied by a supply line connected to at least one “pig” provided with a spray nozzle for the application of the liquid coating material to the chosen surface of an industrial process system. , where the driving force for the movement of the scraping device is provided by a hydraulic actuator motor that drives the traction devices, such as wheels, said actuator capturing a portion of the liquid pressure from the supply line before the coating material is sprinkled from the supplied spray nozzle, said hydraulic pressure being provided upstream of the supply line head by known means such as pumps, compressors or the like. In some embodiments, the pressure that is used to feed the spray nozzle is stopped before being expelled from the nozzle and its pressure energy is used to move the pig forward using wheels driven by a hydraulic motor.

In some embodiments of the invention, a single “pig” can be pulled through a pipe through a supply line that transfers sufficient liquid coating material to the “pig” such that the “pig” absorbent material remains saturated at a level that leaves a very wet sub on the inner walls of the tube, said supply line also being strong enough to provide the necessary pusher force to move the “pig” along the length of the tube or the piping system.

In still other embodiments of the invention, a single “pig” can be pulled through a pipe through a supply line that transfers enough liquid coating material to the “pig” and feeds a spray device provided in the “pig” that atomizes the liquid coating material and directs it to the inner walls of the tube, said supply line being also strong enough to provide the necessary driving force to move the pig along the length of the tube or pipe system.

In some embodiments of the invention, guides can be provided at selected points along the feed tube to keep the feed tube centered in the plane of the pipe cross section. In some interactions of this modality, the guide that centers the feeding tube can be constructed using known steel spring guides, hard disks, or any other means known to those usually skilled in the art.

In some embodiments of the liquid coating invention, comprising at least one metallic compound can be applied to the inner surface of a tube and then exposing the wet surface to an environment that will convert at least part of the compound to at least one metal oxide , for example, by raising the temperature of the wetted surface to a desired temperature by known means.

The alkyl term, as used herein, refers to a straight chain saturated hydrocarbon or branched or cyclic, or a combination thereof, including Ci to C _24, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl, cyclopentyl, isopentyl, neopentyl, n-hexyl, isohexyl, cyclohexyl, 3-methylpentyl, 2,2-dimethylbutyl, 2,3dimethylbutyl, heptila, octyl, nonil, and decila.

The term alkoxyl, as used herein, refers to a straight, branched or cyclic saturated hydrocarbon, or a combination thereof, including aa C ₂ 4, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl , t-butyl, n-pentyl, cyclopentyl, isopentyl, neopentyl, n-hexyl, isohexyl, cyclohexyl, 3-methylpentyl decyl, 2,2-dimethylbutyl, 2,3dimethylbutyl, heptila, octyl, nonylphenol, and in which the hydrocarbon contains a single atom of bonded oxygen that can bind or be bound to another atom or molecule.

The terms alkenyl and alkynyl, as used herein, refer to straight, branched, or cyclic hydrocarbons with at least one double or triple bond, respectively. Alkenyl and alkynyl include, but are not limited to, Ci to C ₂₄ hydrocarbons.

The term aryl or aromatics, as used herein, refers to the monocyclic or bicyclic ring hydrocarbon molecule having double conjugated bonds around the ring. In some embodiments, the ring molecule has 5 to 12 members, but is not limited to these. The ring may be unsubstituted or substituted with one or more identical or different substituents selected independently, wherein the substituents are selected from alkyl, alkenyl, alkynyl, alkoxy, hydroxy and amino radicals and halogen atoms. Aryl includes, for example, unsubstituted or substituted naphthyl and unsubstituted or substituted phenyl.

The term heteroaryl as used herein refers to a monocyclic or bicyclic ring aromatic hydrocarbon molecule having at least one heteroatom selected from O, N, P and S as a member of the ring, and the ring is unsubstituted or replaced with a or more identical or different substituents, independently selected from alkyl, alkenyl, alkynyl, hydroxy, alkoxy, amino, alkylamino, dialkylamino, thiol, alkyl thio, = 0 = NH, = PH, = S, and halogen atoms. In some embodiments, the ring molecule has 5 to 12 members, but is not limited to these.

The term hydrocarbon refers to molecules that contain carbon and hydrogen.

“Equal or“ different ”, when describing three or more substituents for example, indicates combinations in which (a) all substituents are equal, (b) all substituents are different, and (c) some substituents are the same, but different from other substituents.

Suitable metal compounds that form metal oxides include substances such as molecules that contain at least one metal atom and at least one oxygen atom. In some embodiments, metallic compounds that form metallic oxides include metallic carboxylates, metallic alkoxides and metal-β dicetonates.

A. Metallic carboxylates

The metal salts of carboxylic acids useful in the present invention can be produced from any suitable carboxylic acids according to methods known in the art. For example, U.S. Patent No. 5,952,769 to Budaragin discloses suitable carboxylic acids and methods of producing metal salts of carboxylic acids, among other places, in columns 5-6. U.S. Patent No. 5,952,769 is hereby incorporated by reference. In some embodiments, metallic carboxylate can be selected from metallic salts of 2-hexanoic acid. In addition, suitable metal carboxylates can be purchased from chemical suppliers. For example, cerium 2-ethylexanoate (ll), magnesium stearate (ll), manganese cyclohexanobutyrate (ll), and zinc methacrylate (ll) are available from Sigma-Aldrich, St. Louis, MO. See Aldrich Catalog, 2005-2006. Additional metal carboxylates are available, for example, from Alfa Aesar of Ward Hill, MA.

The metallic carboxylate composition, in some embodiments of the present invention, comprises one or more metallic salts of one or more carboxylic acids ("metallic carboxylate"). Suitable metal carboxylates for use in the present invention include at least one metal atom and at least one carboxylate radical -OC (O) R attached to at least one metal atom. As stated above, metallic carboxylates can be produced by a variety of methods known to those usually skilled in the art. Non-limiting examples of methods for the production of metallic carboxylate are shown in the following reaction schemes:

nRCOOH + Me -> (RCOO) _n Me ^{n +} + 0.5nH ₂ (for alkaline earth metals, alkali metals, and thallium).

nRCOOH + Me ^{n +} (0H) n - »· (RCOO) nMe ^{n +} + nH20 (for practically all metals that have a solid hydroxide).

nRCOOH + Me ^{n +} (CO3) 0.5n -> (RCOO) nMe ^{n +} + 0.5nH2O + 0.5nCO ₂ (for alkaline earth metals, alkali metals, and thallium).

nRCOOH + Me ^{n +} (X) n / m -> (RCOO) nMe ^{n +} + n / mHmX (liquid extraction, usable for- practically all metals that have solid salts).

In the reaction schemes mentioned, X is an anion with a negative charge m, such as, for example, halide anion, sulfate anion, carbonate anion, phosphate anion, among others, n is a positive integer, and Me represents a metal atom .

R in the mentioned reaction schemes can be selected from a wide variety of radicals. Suitable carboxylic acids for use in the production of metal carboxylates include, for example:

Monocarboxylic acids:

Monocarboxylic acids where R is hydrogen or unbranched hydrocarbon radicals, such as, for example, HCOOH - formic, CH ₃ COOH - acetic, CH ₃ CH ₂ COOH propionic, CH ₃ CH ₂ CH ₂ COOH (C ₄ H ₈ O ₂ ) - butyric, C ₅ H ₁₀ O ₂ - valeric, C ₆ H ₁₂ O ₂ - capróico, C ₇ Hi ₄ - enantico; additional: caprylic, pelargonic, undecanoic, dodecanoic, tridecylic, myristic, pentadecyl, palmitic, marginal, stearic, and nonadecyl acids;

Monocarboxylic acids where R is a branched hydrocarbon radical, such as, for example, (CH ₃ ) ₂ CHCOOH - isobutyric, (CH ₃ ) ₂ CHCH ₂ COOH - 3-methyl butanoic, (CH ₃ ) ₃ CCOOH - trimethylacetic, including VERSATIC 10 (trade name), which is a mixture of saturated synthetic carboxylic acid isomers, derived from a highly branched C ₁₀ structure;

Monocarboxylic acids where R is a branched or unbranched hydrocarbon radical containing one or more double bonds, such as, for example, CH ₂ = acrylic CHCOOH, CH ₃ CH = CHCOOH - crotonic, CH ₃ (CH ₂ ) ₇ CH = CH ( CH ₂ ) ₇ COOH - oleic, CH ₃ CH = CHCH = CHCOOH - hexa-2,4-dienoic, (CH ₃ ) ₂ C = CHCH ₂ CH ₂ C (CH ₃ ) = CHCOOH - 3,7 dimethylocta-2,6 -dienic, CH ₃ (CH ₂ ) ₄ CH = CHCH ₂ CH = CH (CH ₂ ) ₇ COOH - linoleic, additional: further: angelic, tíglico and elaídico;

Monocarboxylic acids in which R is a branched or unbranched hydrocarbon radical containing one or more triple bonds, such as, for example, CH = CCOOH - propiol, CH ₃ C = CCOOH - tetrol, CH ₃ (CH ₂ ) ₄ C = CCOOH - oct-2-inoic, and stearolic acids;

Monocarboxylic acids where R is a branched or unbranched hydrocarbon radical containing one or more double bonds and one or more triple bonds;

Monocarboxylic acids where R is a branched or unbranched hydrocarbon radical containing one or more double bonds and one or more triple bonds and one or more aryl groups;

Monohydroxymonocarboxylic acids where R is a branched or unbranched hydrocarbon radical containing a hydroxyl substituent, such as, for example, HOCH ₂ COOH - glycolic, CH ₃ CHOHCOOH - lactic, C ₆ H ₅ CHOHCOOH - amidalic and 2-hydroxybutyric acids;

Dihydroxymonocarboxylic acids where R is a branched or unbranched hydrocarbon radical containing two hydroxyl substituents, such as, for example, (HO) ₂ CHCOOH - 2,2-dihydroxyacetic acid;

Dioxicarboxylic acids, where R is a branched or unbranched hydrocarbon radical containing two oxygen atoms each attached to two adjacent carbon atoms, such as, for example, C ₆ H ₃ (OH) ₂ COOH - dihydroxyl benzoic, C ₆ H ₂ (CH ₃ ) (OH) ₂ COOH - orselinates; plus: caffeic and piperic acids;

Aldehyde-carboxylic acids, where R is a branched or unbranched hydrocarbon radical that contains an aldehyde group, such as, for example, CHOCOOH - glyoxalic acid;

Keto-carboxylic acids, where R is a branched or unbranched hydrocarbon radical containing a ketone group, such as CH ₃ COCOOH - pyruvic, CH ₃ COCH ₂ COOH - acetoacetic and CH ₃ COCH ₂ CH ₂ COOH - acids Levulins;

Monoaromatic carboxylic acids, where R is a branched or unbranched hydrocarbon radical containing an aryl substituent, such as C ₆ H ₅ COOH - benzoic acids, C ₆ H ₅ CH ₂ COOH - phenylacetic, C ₆ H ₅ CH (CH ₃ ) COOH - 2-phenylpropanoic, 0 ₆ Η ₅ ΟΗ = ΟΗΟΟΟΗ - 3-phenylacrylic and C ₆ H ₅ C = CCOOH - 3-phenyl-propiol;

Multicarboxylic acids:

Saturated dicarboxylic acids, where R is a branched or unbranched saturated hydrocarbon radical containing a carboxylic acid group, such as HOOC-COOH - oxalic, HOOC-CH ₂ -COOH - malonic, HOOC (CH ₂ ) ₂ - COOH - succinic, HOOC (CH ₂ ) ₃ COOH - glutaric, HOOC (CH ₂ ) ₄ -COOH - adipic; additional: pyelic, suberic, azelaic, and sebacic acids;

Unsaturated dicarboxylic acids, where R is a branched or unbranched hydrocarbon radical containing a carboxylic acid group and at least one carbon-carbon multiple bond, such as, for example, HOOC-CH = CH-COOH - fumaric; plus: maleic, citraconic, mesaconic and itaconic acids;

Polybasic aromatic carboxylic acids, where R is a branched or unbranched hydrocarbon radical containing at least one aromatic group and at least one carboxylic acid group, such as, for example, C ₆ H ₄ (COOH) ₂ - phthalic (isophthalic, terephthalic ) and C ₆ H ₃ (COOH) ₃ - benzyl-tri-carboxylic acid;

Saturated polybasic carboxylic acids, where R is a branched or unbranched hydrocarbon radical containing at least one carboxylic acid group, such as, for example, ethylene diamine Ν, Ν’-diacetic acid, and ethylene diaminetetraacetic acid (EDTA);

Polybasic oxyacids:

Polybasic oxyacids, where R is a branched or unbranched hydrocarbon radical containing at least one hydroxyl substituent and at least one carboxylic acid group, such as HOOC-CHOH-COOH - tartronic, HOOC-CHOH-CH ₂ -COOH malic, HOOC-C (OH) = CH-COOH - oxaloacetic, HOOC-CHOH-CHOH-COOH - tartaric and HOOC-CH ₂ -C (OH) COOH-CH ₂ COOH - citric acid.

In some embodiments, monocarboxylic acid comprises one or more carboxylic acids having the formula I below: R ° -C (R ") (R ') - COOH (I) where:

R ° is selected from H or C 1 to C ₂₄ alkyl groups; and

R 'and R ”are each independently selected from H and C 1 to C 24 alkyl groups;

where the alkyl groups of R °, R 'and R ”are optionally and independently substituted with one or more substituents, which are the same or different, selected from hydroxyl, alkoxy, amino, and aryl radicals, and halogen atoms.

Some suitable alpha branched carboxylic acids typically have an average molecular weight in the range of 130-420. In some embodiments, carboxylic acids have an average molecular weight in the range of 220-270. Carboxylic acids can also be a mixture of tertiary and quaternary carboxylic acids of formula I acids. VIK acids can also be used. See U.S. Patent No. in columns 6, II. 12-51.

Either one of a single carboxylic acid or a mixture of carboxylic acids can be used to form the metal carboxylate composition. In some embodiments, a mixture of carboxylic acids is used. In still other embodiments, the mixture contains 2-ethylexanoic acid where R ° is H, R ”is C ₂ H ₅ and R 'is C ₄ H ₉ in the formula (I) above. In some embodiments, this acid is the lowest boiling point acid contained in the mixture. When a mixture of metal carboxylates is used, the mixture has a wider evaporation temperature range, making it more likely that the evaporation temperature of the mixture will overlap with the decomposition temperature of the metal carboxylate, allowing the formation of a solid layer of metallic oxide. In addition, the possibility of using a mixture of carboxylates avoids the need and costs of purifying an individual carboxylic acid.

For those embodiments of the present invention that involve a cleaning composition comprising one or more carboxylic acids, any of the above carboxylic acids may be appropriate, alone or in combination.

B. METALLIC ALKOXIDS

Metal alkoxides suitable for use in the present invention include at least one metal atom and at least one -OR ₂ alkoxide radical attached to at least one metal atom. Metal alkoxides include those of formula II:

M (OR ² ) _z (II)

Where M is a valence metal atom z ⁺ ;

z is a positive integer, such as 1, 2, 3, 4, 5, 6, 7 and 8;

R ² can be the same or different and are independently selected from radicals unsubstituted and substituted alkyl, unsubstituted and substituted alkenyl, unsubstituted and substituted alkenyl, unsubstituted and substituted alkynyl, unsubstituted and substituted heteroaryl, and unsubstituted and substituted aryl, where the alkyl, alkenyl, alkynyl, heteroaryl and aryl substituted radicals are substituted with one or more identical or different substituents, independently selected from halogen, hydroxyl, alkoxyl, amino, heteroaryl, and aryl radicals.

In some modalities, z is selected from 2, 3 and 4.

Metal alkoxides are available from Alfa-Aesar and Gelest, Inc., of Morrisville, PA. Lanthanide alkoxides such as those from Ce, Nd, Eu, Dy, Er and are marketed by Kojundo Chemical Co., Saitama, Japan, as well as Al, Zr and Hf alkoxides, among others. See, for example, http://www.kojundo.co.jp/English/Guide/material/lanthagen.html.

Examples of metal alkoxides useful in embodiments of the present invention include methoxides, ethoxides, propoxides, isopropoxides and butoxides and their isomers. The alkoxide substituents on a given metal atom are the same or different. Thus, for example, metal dimethoxide diethoxide, diisopropoxide t-butoxide methoxide and similar metal alkoxides can be used. Suitable alkoxide substituents can also be selected from:

1. aliphatic series alcohols from methyl to dodecyl including branched and isostructured.

2. Aromatic series alcohols: benzyl alcohol - C ₆ H ₅ CH ₂ OH; ethyl alcohol-phenyl C ₈ Hi ₀ O, phenyl-propyl alcohol - C9H12O, and so on.

Metal alkoxides useful in the present invention can be made according to various methods known in the art. One method includes the conversion of metal iodides to metal alkoxide in the presence of alcohol and its corresponding base. For example:

MX _Z zHOR ² M (0R ² ) _z + zHX where M, R ² , and z are as previously defined for formula II, and X is a halide anion.

C. METAL β-DICETONATES

Metal β-diketonates suitable for use in the present invention contain at least one metal atom and at least one β-diketone of formula III as a binder:

on what

R ³ , R ⁴ , R ⁵ and R ⁶ are the same or different and are independently selected from hydrogen, unsubstituted and substituted alkyl groups, unsubstituted and substituted alkoxy, unsubstituted and substituted alkenyl, substituted and unsubstituted alkynyl, unsubstituted heteroaryl and substituted, substituted and unsubstituted aryl, carboxylic acid groups, ester groups having unsubstituted and substituted alkyl, and combinations thereof mentioned, in which alkyl, alkoxy, alkenyl, alkynyl, heteroaryl radicals are substituted, and aryl radicals are substituted with one or more equal or different substituents, independently selected from halogen atoms, hydroxyl, alkoxy radicals, amino acids, heteroaryl, and aryl radicals.

It is understood that the β-diketone of formula III can assume different isomeric and electronic configurations before and while chelated to the metal atom. For example, free β-diketone may show isomerism enolate. In addition, β-diketone cannot maintain strict carbon-oxygen double bonds when the molecule is attached to the metal atom.

Examples of β-diketones useful in embodiments of the present invention include acetylacetone, trifluoroacetylacetone, hexafluoracetylacetone, 2,2,6,6-tetramethyl-3,5heptanedione, 6,6,7,7,8,8,8-heptafluor-2, 2-dimethyl-3,5-octanedione, ethyl acetoacetate, 2-methoxyethyl acetoacetate, benzoyltrifluoracetone, pivaloyltrifluoracetone, benzoylpyruvic acid, and methyl-2,4-dioxo-4-phenylbutanoate.

Other binders are possible in the metal β-diketonates useful in the present invention, such as, for example, alkoxides such as -OR ² , as defined above, and dienyl radicals, such as, for example, 1,5-cyclooctadiene and norbornadiene

Metal β-diketonates useful in the present invention can be made according to any method known in the art, β-diketones are known as metal chelating agents, facilitating the synthesis of diketonate from easily available metal salts.

Metal β-diketonates are available from Alfa-Aesar and Gelest, Inc. In addition, Strem Chemicals, Inc. of Newburyport, MA, markets a wide variety of metal β-diketonates on the Internet at http: //www.strem .com // code template.ghc? directcvdindex.

In some embodiments of the invention, doors can be provided inside the external surfaces of an included component of an industrial system, for example, in the walls of a pipe, said doors providing a means for the application of a liquid in which the pressure within the tube to be coated is reduced to a level sufficient to produce at least partial vaporization of the liquid when it is applied to the inner parts of the tube, so that the vaporized part of the liquid condenses on the inner surface of the tube and provides a well-wetted surface . In some embodiments, multiple application ports for delivering liquid liner material to the interior at low pressure of a tube can be provided along the length of a tube composition, for example, and a selected fluid delivered to each port by means of known distributors, pipes, or other means of transferring fluid such that sufficient liquid material is applied to the inside of the tube and partially or totally vaporized where the condensation of the vapors of the coating material over the inner surfaces of the tube to establish a desired coating on the inner surfaces of the tube. In some interactions of this modality, the existing orifices provided in a thermocouple placement system can be used, either thermally or permanently, as introduction doors through which a coating material can be introduced into a sealed system, said material of coating being then at least partially vaporized by means of a reduction in the pressure existing within the sealed system.

In some embodiments of the invention, wetting the inner surface of the tube is followed by a drying phase where heat is supplied to the surfaces using suitable methods to perform the conversion of at least a portion of the liquid delivered to a metallic coating oxide. As described, suitable methods for converting at least a portion of at least one metallic compound to at least one metal oxide include, but are not limited to, washing the wet system or component thereof with the gas at high temperature, heating by induction of system or component walls, heating with one or more lasers, microwave emitters, infrared emitters, or plasma; exposure to flame, for example, from the outer walls of the system or component, exposing the wet system or component to the thermal energy of one or more exothermic reactions, and combinations of those mentioned.

In some embodiments of the invention, a supply flexitube can be provided along the extension of the inner side of a tube where the supply tube has small holes provided on its exterior that lead to its interior such that when the pressure inside the tube is greater that the pressure outside the tube, the fluid or gases contained in the tube are caused to move from the inside of the supply tube to the interstitial space between the outer surface of the tube and the inner surface of the tube such that at least a portion of the fluid condenses over the inner surface of the tube. In some embodiments of the invention, the pressure within the interstitial space between the flexitube and the inner wall of the tube can be provided with a sufficient vacuum level such that any liquid inside the flexitube will be drawn into the interstitial space and then deposited on the inner surfaces of the tube. At least a portion of that fluid coming out of the flexible tube will attach itself properly to the inner surface of the tube and thus can be converted to a metal oxide coating through some secondary process, such as drying in dehydrated air, heating the wet surface to a temperature, exposing the liquid coating to ultraviolet light, etc.

In some embodiments of the invention, a coating can be formed inside a tube or passage through the use of a spray nozzle fed by a flexible hose. For example, a composition comprising at least one metallic compound is supplied at a pressure sufficient to achieve uniform application of the composition to the internal surface of the passage, such as by dispersion through one or more spray nozzles attached to at least one "pig" . Then, at least one metallic compound can be converted to a coating on the internal surfaces of the passage through a heating process provided by an infrared emitter that is placed inside the passage very close to the wetted area.

In some embodiments, at least one IR emitter is mounted on a “pig”, which also supports a spray nozzle and a means for keeping the spray nozzle and IR emitter centered in the passage. These means include, in some embodiments, guides such as flexible fingers or other structures suitable for centralizing devices within passages, such as those familiar to those usually skilled in the art.

In some implementations, such guides transit against the inner walls of the “upstream” passage of the spray nozzle so that the contact of the guides with the inner walls of the spray passage does not remove the composition from the inner surface of the tube.

In some implementations, at least one IR emitter is located downstream of the spray nozzle so that the spray droplets of the composition are fully dispersed and in contact with the interior wall of the passage from the previous to the electromagnetic radiation, the IR emitter becoming very close to the surface and thus provides a means to reduce the amount of spray carried by the air that can maintain contact with the IR emitter itself. In some embodiments, at least one IR emitter is located on the same “pig” as one or more spray nozzles. In other embodiments, the at least one IR emitter is located in a “pig” other than the “pig” that comprises one or more spray nozzles.

In some embodiments, a feed of an inert gas can be provided to create a non-oxidizing atmosphere for the process of heating the conversion liquid and the underlying material such that oxidation of the inner wall of the passage is reduced or eliminated.

In some embodiments, the spray nozzle is fed with liquid under pressure through a flexible line, the IR emitter is supplied with electrical energy through suitable electrical wires.

In some embodiments, the guides and the spray nozzle (s) can be located upstream of the IR emitter and the liquid supply can be provided by a pipe or tube that extends outward from the assembly through the piping system and out to a reservoir with a fluid pump and can also have an electrical power cord that extends out of the assembly through the piping system and up to an electrical source suitable for the power requirements of the emitter IR and other devices mounted to the assembly.

In other embodiments of the invention, a liquid composition comprising at least one metallic compound can be applied to the selected surfaces of a fluid flow system using a motorized “pig” that is equipped with at least one spray nozzle and one or more spray units. traction devices where the motorized “pig” is moved through a piping system and sprays the composition inside the tube. In some embodiments, the composition can be supplied through a reservoir provided within the “pig” set. Means of providing pressure to the nozzle are also provided in known ways, such as stored air pressure, electric pumps, or the like, and the driving force for the drive is provided from the stored air pressure, electric pumps, or similar. In this implementation, the “pig” can travel in a chosen direction with the spray head to be, at its rear end, thus leaving an application, without interrupting the liquid composition on the chosen surface of the piping system in which it traveled. In some interactions of the present modality, the “pig” can be moved through a rope or cable connected to the “pig” set at a selected point.

In other embodiments, the driving force to move the set of “pigs” through the system to apply a composition to the internal surface of the passage zone (s) can be provided by the voltage applied to the liquid supply lines, electrical supply wires, cable separated from enough strength to pull the assembly, or a combination of those mentioned. Voltage is supplied by known means, in some embodiments, such as an electric motor driven by a reel device mounted outside the piping system and controlled by known means to provide the desired transit speed of the “pig” assembly at the same time. that providing the desired liquid coating material at the desired application rate along the length of the supply line and providing any necessary electrical current flow at a voltage chosen through optional electrical supply wires that run from the reel device to the assembly. In some implementations of this modality, the casing assembly may first pass to a selected location within a passage piping, or piping system through the use of gas pressure acting against a scraping device connected to the casing assembly such that the scraping acts as a partial or complete plug of the pipe cross section and, when pressure is applied to the inside of the pipe upstream of the scraping device, the difference in pressure between the upstream and downstream parts with respect to the scraping device scraping causes it to move towards the lowest pressure zone. In this way, the scraping device and the attached coating assembly, which may incorporate guides, spray nozzle, and IR emitter, or a combination thereof, can be transferred to a selected location within the piping system and then collected using the voltage provided by at least one of the power lines or cables.

In some embodiments of the invention, there may be a vaporization phase created after the liquid coating material is applied to the inner surface of the tube where the wet surfaces are exposed to an ambient pressure close to or less than the vapor pressure of the liquid coating material , resulting in phase change of at least part of the liquid coating materials from the liquid phase to the vapor phase, followed by an increase in absolute pressure in the system causing at least a part of the vaporous material coating phase to condense over at least part of the inner surfaces of the tubes, said process greatly helping in the uniform distribution of the coating material over the inner surfaces of the tube. In some implementations of this modality, vaporization of at least part of the liquid coating material can be achieved through the use of a vacuum pump system that is fluidly connected to the interior volume by a piping system and left to evacuate the interior volume created by the inner surfaces of the tube and the corresponding seals or plugs that may be provided at any open ends or ports within the piping system. In additional implementations of this modality, the reduction of local pressure inside a piping system and its complete or partial restoration to ambient pressure can be achieved through known control systems using one or more vacuum pumps, or through the use of doors and valves operated by manual, semi-automatic or automatic means known to those usually versed in the technique of industrial process control. In some embodiments, the required vacuum can be made by any of a variety of known vacuum production systems that include, but are not limited to, pumps, blowers, molecular entrainment systems, turbo-molecular systems, cryosorption processes, ion sputtering pump, and the like.

In some interactions of this modality, the pressure reduction inside the tube can be provided through a reduction in the temperature of the piping system while the system is completely sealed, taking advantage of the natural reduction in pressure and volume that will occur as a system sealed is allowed to cool and the internal gases contract in accordance with the Ideal Gas Law, expressed as,

PV = nRT where:

P = pressure

V = volume n = number of moles of gas

R = gas constant (8,314 m ³ .Pa.K ' ¹ mol' ¹ )

T - temperature such that a reduction in the temperature of a selected molar quantity of the gas within a sealed system will result in the reduction of its absolute pressure, proportional to the reduction in temperature.

In this implementation of a modality, the high temperature used to convert the liquid coating material to a usable surface treatment can also be used to create the vacuum required for the dispersion of the next coating application cycle by first heating the piping system using a suitable heating medium, for example, an oven, then sealing the ends of the tube and any ports, capturing the ambient air inside the tube along the length of its length, then leaving the tube and the air contained to cool to a desired temperature at which the contraction of the air captured within the sealed tube can induce the pressure to drop to desired levels, then the introduction of a liquid coating material through chosen ports or passages can result in vaporization of the liquid. In some interactions of this modality, additional evacuation may be necessary to achieve the desired vacuum levels.

In some embodiments, the low pressure that develops within the sealed piping system may need to be bled to prevent the pressure level from falling below a selected level, which can induce unwanted stresses or other vacuum related problems to be imposed to the piping system. In some interactions of this modality, the tube can be filled with a selected gas, such as an inert gas, before sealing and cooling operation so that the liquid coating material, once introduced into the piping system, is vaporized in a atmosphere other than normal air inside the tube. In an iteration of this modality, an inert gas, such as nitrogen, can be used to completely or partially fill the tube, and provide an inert atmosphere for vaporization of the liquid coating material such that the subsequent heating operation results in the conversion of the liquid material in the form of a coating with the desired characteristics. In other interactions of this modality, a reducing gas, such as hydrogen, can be introduced into the piping system before cooling and injection of the liquid coating material, such that the subsequent heating operation results in the conversion of the liquid material in the form of a coating. with the desired characteristics. In some interactions of this modality, the heating process can be achieved using known methods, such as external heating via induction, internal heating with gas or liquid flow at the chosen temperature, through microwave emissions, by means of flames outside or in system, and similar methods.

In one embodiment of the invention, a piping system can be coated using the vapor deposition of a coating material, first sealing a selected segment of a piping system or component, then evacuating the internal volume of the sealed piping system to a selected vacuum level, then, by introducing a liquid formulation composed of the desired coating material, said liquid formulation becomes vaporized as it is introduced to the internal volume evacuated from the piping system in which sufficient amount of liquid it is allowed to pass inwards the volume of the piping system to achieve full or partial saturation of the gases remaining in the internal volume, then through the introduction of a selected gas, for example nitrogen, the pressure within the closed pipe system allowed to rise to a selected level, resulting in condensation of the ma vapor-phase coating material in the form of a liquid-phase coating material, said condensation resulting in uniform wetting of the internal surfaces of the sealed system. In some implementations of this modality, the condensation process is followed by heating these wet surfaces to a temperature sufficient to convert at least a portion of the at least one metallic compound into at least one metal oxide coating.

In some interactions of this modality, several layers of similar or different metal oxide coating can be achieved with repeated vaporization cycles and by the condensation process described above. In other interactions of this modality, additional layers of coating material can be applied to a chosen surface using a combination of known methods to carry out the construction of the desired final coating, for example, the spraying of at least one metallic compound and then its Conversion to at least one metal oxide can be followed by the vapor deposition of a subsequent film which can be followed by additional layers using a selected application method described within that application or using an alternative method as desired.

In some embodiments, the method of the invention may include a pre-application of the cleaning step before applying the composition. In these embodiments, the invention involves the application of one or more cleaning materials, which can be in the vapor, liquid, semi-solid phase, or a combination of these, to at least part of the surfaces of the final system, followed by a wash and drying at a drying temperature. The cleaning technique can be of the type used to clean surfaces before coating, electroplating, painting, or similar surface treatments. The pre-registration cleaning step may also include a pickling operation using known chemicals and a process for preparing the surface (s) for the coating.

Certain embodiments employ a cleaning composition that comprises one or more acids. Other embodiments employ a cleaning composition that comprises one or more carboxylic acids. In additional modalities, one or more "pigs" contact a cleaning composition being placed in launch communication with the tube to be treated. Then the "pig (s)" Then the "pig" (s) is guided through the tube, allowing the cleaning composition to maintain contact and thereby clean the inside of the tube. Optionally, the same or different pigs pass through the tube more than once, contacting the inner surface of the tube with the same or different cleaning composition. For example, a first cleaning composition can be an acid, and a second cleaning composition can be water or a mild base to neutralize the acid. Optionally, the cleaning composition (s) is removed by any suitable method, such as, for example, washing with liquid, such as water, dry air, and / or nitrogen, and / or by heating the environment inside the tube to expel the cleaning composition (s). In one embodiment, the environment within the tube contacted with a cleaning composition is heated to about 400 ° C to about 427 ° C in the presence of nitrogen, cooled, and purged with nitrogen or dry air. Heating can be done in the presence of nitrogen, in certain cases, to limit the reaction of the surface with oxygen and / or water at the heating temperature. The cleaning composition is substantially removed when any amount or residue remaining may not interfere with the use of the tube or the subsequent treatment (such as metal oxide formation) of the tube.

In another embodiment, spherical sponges are soaked with a cleaning composition and individually passed through a tube to be cleaned and removed at the other end of the tube, driven by compressed air. After one, two, three, four or more passes, the tube is sealed, flushed with nitrogen and heated to remove the cleaning composition. After cooling, the tube can be cleaned additionally, or a coating composition can contact the inside of the tube in accordance with other embodiments of the present invention disclosed herein.

In this way, some modalities provide a method for cleaning the inner surface of a pipe, comprising:

placing a first “pig” as close to the inner surface of the tube, where the first “pig” is a compressible sponge with a diameter in an uncompressed state at least about 1.4 times the largest inner diameter of the tube;

applying a first cleaning composition to the internal surface with the first "pig", thereby cleaning the internal surface, where the first cleaning composition comprises a carboxylic acid; and substantially removing the first cleaning composition from the inner surface.

In other embodiments, the prior method also includes, before substantially removing the first cleaning composition,

Place a second “pig” as close to the inner surface of the tube; and apply a second cleaning composition to the inner surface with the second “pig”.

where substantially removing the first cleaning composition also substantially removes the second cleaning composition.

The diameter, in this case, refers to the diameter relative to the cross section of the pipe to be treated. Thus, an oblong or projectile-shaped “pig” has a diameter relative to the inner diameter of the tube, considering the orientation that the “pig” will adopt inside the tube. The diameter, in general, can be any suitable diameter that allows the pig to maintain a seal in the tube, such that a fluid such as compressed air can propel the pig along the length of the pipe. In some cases, the diameter of the compressible sponge is about 1.4 times, about 2 times, or about 3.5 times the maximum internal diameter of the tube to be treated. The diameters refer to the sponge in an uncompressed state. In certain embodiments, the compressible sponge is spherical in an uncompressed state.

Some other embodiments employ a cleaning composition that comprises one or more carboxylic acids. In additional embodiments, the cleaning composition comprises acetic acid, formic acid, propionic acid, 2-ethylexanoic acid, or a combination of two or more of those mentioned. In even more embodiments, the first cleaning composition consists essentially of 2-ethylexanoic acid. When describing a first and second cleaning composition, the second cleaning composition can be the same or different from the first cleaning composition.

Additional modalities provide a method for the formation of at least one metal oxide on an internal surface of a processing or transport system for an industrial fluid or component, including:

place at least one first “pig” as close to the internal surface of the processing or transport system for industrial fluid or its components;

apply at least one cleaning composition to the internal surface with at least one first “pig”;

substantially removing at least one cleaning composition from the internal surface, placing at least one second "pig" as close to the internal surface of the processing or transportation system of an industrial fluid or its component;

apply at least one metallic compound to the internal surface with at least one second “pig”; and converting at least part of the metallic compound to at least one metallic oxide.

Still other embodiments of the present invention employ at least two applications of the same or different metallic compounds on the internal surface of an industrial fluid processing or transport system, such as a tube, where two different temperatures are used. Thus, certain modalities provide a method for the formation of at least one metal oxide on an internal surface of a processing or transport system for an industrial fluid or its component, comprising:

Place at least one first “pig” as close to the processing or transport system for industrial fluid or its components;

apply at least one first metallic compound to the internal surface with at least one first “pig”;

heating the interior surface environment to a temperature ranging from about 400 ° C to about 427 ° C;

place at least one second “pig” as close to the internal surface of the processing or transport system as an industrial fluid or its components;

apply at least a second metallic compound to the internal surface with at least a second “pig”;

where the at least one first metallic compound and at least one second metallic compound are the same or different; and heating the environment of the inner surface to a temperature ranging from about 438 ° C to approximately 604 ° C, forming at least one metal oxide on the inner surface.

Some embodiments of the present invention provide a method for reducing or preventing fouling on a sensor surface, or a component thereof. Other embodiments offer a sensor comprising at least one surface comprising at least one metal oxide. In additional embodiments, the at least one surface of the sensor comprises at least one metal oxide, wherein at least part of the at least one metal oxide is present in a diffuse coating. Sensors may contain more than one part, including but not limited to the sensor element (s), assembly of structures, and means of evaluating response such as, for example, electrical circuits that may be in a protective coating. Each of these parts has surfaces that can benefit from a metal oxide coating; one or more of these surfaces can be coated according to the invention. Sensors that appear in the modalities of the present invention include, but are not limited to, displays, for example, a viewing glass in a boiler, thermocouples, thermal resistance devices (RTDs), pressure sensors, flow and mass flow sensors , air speed sensors, piezoelectric sensors, photo-optical combustion sensors, high temperature chromatographs, optical sensors, UV sensors, infrared sensors, electromagnetic field sensors, electromagnetic wave sensors, radiation sensors, toxic chemical sensors , gas analyzers, oxygen sensors, nitrogen sensors, NOx sensors, SOx sensors, CO ₂ sensors, CO sensors, soot sensors in diesel exhaust, other soot sensors, H ₂ S sensors and humidity sensors, among others. Care must be taken that the application of the metallic compound and the conversion to at least one metal oxide are achieved in order to avoid damage to the sensor, or to avoid inhibiting the operation of the sensor. Damage can be minimized or avoided, in some modalities, by converting to a lower temperature, or without substantially heating the surface. Alternatively, in other embodiments, non-sensitive elements on the surface can receive at least a metal oxide coating before the sensitive element (s) is mounted inside the sensor.

Some embodiments of the present invention provide a metal oxide coating on a surface that is subject to coke formation. Such surfaces include, but are not limited to one or more surfaces of:

The heaters, heat exchangers, vacuum tower, and the tubes that contact the heaviest fractions in a crude oil unit or a vacuum unit;

the furnace, heater tubes, furnace outlets, and tubes from an ethylene cracking unit;

the heaters, heating tubes, fractionator bottoms, extractor bottoms, heat exchangers, and tubes from a delayed coking unit or a viscosity breaker;

the cyclone immersion legs and the reactor separating deflectors, the overhead line of the reactor, the exhausted catalyst return line, the inlet of the catalyst regenerator, and the upper and lower fractionator trays of a fluid catalytic cracking unit;

the heaters, heating tubes, reactors, product tubes, catalyst transfer tubes, and tubes in a fixed bed catalytic reform unit; and the reactors, heaters, heat exchangers, and pipes of a syngas generation unit.

Other modalities provide a metal oxide coating on a surface that is subject to corrosive attack by one or more species present in the process flow. Such surfaces include, but are not limited to one or more surfaces of:

the furnaces, towers, separators, coolers, heat exchangers, and pipes of a crude oil unit or a vacuum unit;

the fractionators, separators, compressors, heat exchangers, and tubes of a delayed coking unit;

a fractionator and pipes from there a fluid catalytic cracking unit;

in the extracting drums, tubes, compressors, coolers, and heat exchangers of a recovery unit for light products from catalytic cracking;

the heat exchangers, product separators, de-buterizer, overhead condensers, overhead drums, and tubes from a continuous catalytic reform unit;

reactors, heaters, water washers, separators, hydrogen recycling compressors, separators, heat exchangers, pumps and pipes from a hydrotreating, hydrodesulphurization, or hydrocracking unit;

the trays, tubes, pumps, and the bottom of a sulfuric acid alkylation unit, including the outer surfaces of the tubes that may be confined in isolation;

the decanter, acid regenerator, vaporizer, acid fractionator, cooler, separators, condensers, recyclers, heat exchangers, defluorizers, KOH treaters, pumps and pipes of an HF or sulfuric acid alkylation unit; and the reactor, separator, pumps and pipes of a biodiesel refining unit.

One usually skilled in the art will notice that more than one mechanism can operate to degrade the same surface. Thus, the previous modalities do not suggest exclusive mechanisms for any type of surface.

Still other embodiments of the present invention provide methods for reducing or preventing combustion build-up on a flame-heated surface of a fluid processing or transport system, or a part of it. This combustion build-up can be of any material that deposits on surfaces, including, for example, slag, scale, coke, soot, and combinations thereof. A flame-heated surface includes any surface exposed to combustion of fuel and its products, such as, for example, surfaces exposed to fire, smoke, soot and / or combustion gases, even if that surface is not contacted directly by a flame. Such surfaces include, but are not limited to, interior furnaces, preheaters, coolers and chimneys; boiler exteriors, heater tubes, and flame-heated reactors, fuel ducts, as well as, valves, fans, burners, combustion control devices, ash ducts and as close to the combustion area. A flame-heated surface does not necessarily include a fluid process coming into contact with surfaces. To illustrate, it is contemplated that heat is transferred from the flame-heated surface through the reaction vessel wall to the contact surface with the process fluid. Thus, a vessel wall generally has two surfaces, the flame-heated surface and the contact surface with the process fluid.

Additional modalities provide methods to reduce or prevent the fouling of at least one metallic surface of a combustion engine system, or a part of it. Combustion engine systems include, but are not limited to, internal combustion engines, two-stroke engines, four-stroke engines, gasoline engines, diesel engines, turbo-propelled engines, jet engines, gas turbines and engines rocket. The metal surfaces used include, but are not limited to, jet, turbo, turbofan, ram jet, scram jet, and turbine engine surfaces including intake, compressor, turbine, vanes, stoves, afterburners, nozzle, vector surfaces thrust, and fuel supply components; internal surfaces of combustion engines include pistons, rotors, cylinders, housings, piston rings, gaskets, segments, cylinder heads, valve heads, valve feet, valve seats, valve faces, valve train components, meats , impeller rods, meat followers, rockers, valve springs, valve guides, combustion chambers, crankcases, intake system components, supercharger components, exhaust manifolds, recirculating gas exhaust pipes and valves, turbocharger components, catalytic converter components, exhaust pipes, fuel injectors, and fuel pump; and rocket engine surfaces including intake, fuel delivery systems, fuel combustion zones, and the thrust vector surfaces. In some embodiments, the metal oxide layer on the metal surface of a combustion engine system is an oxidizing coating. In additional embodiments, the metal oxide coating still comprises at least one metal. Metals that may be desired, such as for catalytic purposes, for example, include, but are not limited to, platinum, palladium, rhodium, nickel, gold, cerium, silver, zinc, lead, ruthenium rhenium, and combinations of two or more of the same.

Still other embodiments provide a fluid processing or transport system that comprises at least one surface comprising at least one metal oxide coating, the system having a large size. A large size is useful for commercial fouling processes. Industrial systems for processing or transporting liquids include, but are not limited to, oil refineries; oil refinery subsystems such as crude units, atmospheric units, vacuum units, delayed coking devices, fluid catalytic crackers, fixed bed catalytic cracking, continuous catalytic reformers, naphtha reformers, hydrotreaters, hydrocrackers, alkylators including acid alkylators sulfuric and HF alkylators, amine treaters, sulfur recovery units, acid water separators, isomerization units and hydrogen reform units; industrial water treatment units, water cooling systems such as those found in industrial manufacturing units and energy production units; desalination units; and processing systems found in the manufacture of dyes, the manufacture of cosmetics, the processing of foods, the manufacture of chemicals, the manufacture of pharmaceuticals and the like.

In some embodiments, the surface of the fluid processing or transport system for receiving a metal oxide coating in accordance with the present invention has a surface greater than about 9.29 m ² (100 ft ² ). In other modalities, the surface varies from an area of about 9.29 m ² (100 ft ² ) to about 46.45 m ² (500 ft ² ), between about 46.45 m ² (500 ft ² ) to about 92.90 m ² (1000 ft ² ), between about 92.90 m ² (1000 ft ² ) to about 929.03 m ² (10,000 ft ² ), between about 929.03 m ² (10,000 ft ² ), up to about 1858.06 m ² (20,000 ft ² ), between about 1858.06 m ² (20,000 ft ² ) up to about 20,000 square meters to about 4645.17 m ² (50,000 ft ² ), between about 4645.17 m ² (50,000 ft ² ) to about 9290.34 m ² (100,000 ft ² ), between about 9290.34 m ² (100,000 ft ² ) to about 92903.40 m ² (1,000,000 ft ² ), between about 929034,21 m ² (10,000,000 ft ² ) up to about 2.59 km ² (1 mile ² ), between about 2.59 km ² (1 mile ² ) up to about 12.95 km ² (5 miles ² ), between about 12.95 km ² (5 miles ² ) up to about 25.90 km ² (10 miles ² ), or greater than 25.90 km ² (10 miles ² ).

The surface to be treated according to the invention can also be pre-treated, in other embodiments, before applying the composition. In some cases, the surface may be subjected to chemical corrosion according to known methods, for example, with an acid wash comprising nitric acid, sulfuric acid, hydrochloric acid, phosphoric acid, carboxylic acid, or a combination of two or more same, or with a basic wash comprising sodium hydroxide or potassium hydroxide, for example. In other cases, the surface can be mechanically machined or polished, with or without the aid of one or more agents such as chemical reagents, abrasives and polishing agents, to make the surface rougher, or smoother. In still other cases, the surface can be pre-treated, such as by carburizing, nitriding, painting, powder coating, electroplating, or anodizing. Thin films of chromium, tin and other elements, alone or in combination, can be deposited in some modalities. Methods for depositing thin films are well known and include chemical vapor deposition, physical vapor deposition, molecular beam epitaxy, plasma spray, electroplating, ion impregnation, and others.

In some embodiments of the present invention, a metallic compound comprises a transition metal atom. In other embodiments, a metallic compound comprises a rare earth metal atom. In additional embodiments, the composition of the metallic compound comprises a plurality of metallic compounds. In some embodiments, a plurality of metallic compounds comprises at least one rare earth metal compound and at least one transition metal compound, while in other embodiments, a plurality of metal compounds other than at least one earth metal compound rare and at least one transition metal compound. Metal carboxylates, metal alkoxides and metal-β dicetonates can be selected for some embodiments of the present invention.

In additional embodiments, a mixture of metal compounds comprises a metallic compound as its main component, and one or more additional metallic compounds, which can function as stabilizing additives. Stabilizing additives, in some embodiments, include trivalent metallic compounds. Trivalent metallic compounds include, but are not limited to, chromium, iron, manganese, nickel and compounds. A metallic compound composition, in some embodiments, comprises both cerium compounds and chromium compounds.

In some embodiments, the metallic compound which is the main component of the metallic compound composition contains an amount of metal ranging from about 65 to about 97% by weight, or from about 80 to about 87% by weight. weight of the total weight of metal in the composition. In other embodiments, the amount of the metal that forms the main component of the metal compound composition ranges from about 90 to about 97% by weight of the total metal present in the composition. In still other embodiments, the amount of the metal that forms the main component of the metallic compound composition ranges from about 97 to about 100% by weight of the total metal present in the composition.

The metallic compounds that can function as stabilizing additives, in some embodiments, may be present in amounts such that the total amount of the metal in metallic compounds that are the stabilizing additives is at least 3% by weight, in relation to the total weight of the metal in the composition of the metallic compound. This can be achieved in some embodiments, using a single stabilizing additive or several stabilizing additives, as long as the total weight of the metal in the stabilizing additives is greater than 3%. In other embodiments, the amount of the stabilizing metal is less than 3% of the total metal weight in the composition of the metallic compound. In still other embodiments, the total weight of the metal in the stabilizing additives ranges from about 3% to about 35% by weight. In still other embodiments, the total weight of the metal in the stabilizing additives ranges from about 3 to about 30% by weight, relative to the total weight of the metal in the composition of the metallic compound. In other embodiments, the total weight range for the metal in the stabilizing additives ranges from about 3 to about 10% by weight. In some embodiments, the total weight range for the metal in the stabilizing additives is about 7 to about 8%, by weight, relative to the total weight of the metal in the composition of the metallic compound. Still other embodiments provide the stabilizing metal in an amount greater than about 35% by weight relative to the total weight of the metal in the composition of the metallic compound.

The amount of metal in the composition of the metallic compound, according to some modalities, varies from about 20 to about 150 grams of metal per kilogram of composition of the metallic compound. In other embodiments, the amount of metal in the metal compound composition ranges from about 30 to about 50 grams of metal per kilogram of metal compound composition. In additional embodiments, the composition can contain metal compounds from about 30 to about 40 grams of the metal per kg of composition. Amounts of metal less than 20 grams of metal per kg of the metal compound composition or greater than about 150 g of metal per kg of the metal compound composition can also be used.

The metallic compound can be present in any suitable composition. Very finely divided powder, nanoparticles, solution, suspension, multi-phase composition, gel, steam, aerosols and paste, among others, are possible.

The metallic compound composition may also include nanoparticles in the average size range less than 100 nm and being composed of a variety of elements or a combination thereof, for example, AI ₂ O ₃ , CeO ₂ , Ce ₂ O ₃ , TiO ₂ , ZrO ₂ and others. In some cases, nanoparticles can be divided, clustered, or a mixture of dispersed and clustered nanoparticles. The nanoparticles may have applied a negative or positive charge to them to aid dispersion. In addition, dispersing agents, such as known acids or surface modifying agents can be used. The presence of nanoparticles can decrease the porosity of the final coating; the level of porosity generally decreases with increasing quantity and decreasing the size of the included nanoparticles. The porosity of the coating can also be influenced by the application of additional coating layers according to the process of the invention; porosity generally decreases with an increasing number of layers. In some embodiments, the nanoparticles can first be mixed with a liquid and then mixed with the composition of the compound; this method provides a means to create a fine dispersion of a first liquid that maintains its dispersion when mixed with a second or third liquid. For example, nanoparticles of selected elements, oxides, molecules, or alloys can be dispersed in a first liquid and, after a desired quality of dispersion is achieved, the nanoparticles in the first liquid can be mixed with the liquid composition of the metallic compound before exposing the final composition to an environment that will convert at least a portion of the metallic compound (s) into metal oxides. The result can be a denser film, with reduced porous sites.

The application of the metallic compound composition can be carried out by several processes, including those of immersion, spraying, washing, vapor deposition, printing, lithography, rolling, rotating coating, brushing, scraping (for example, with a fabric pig) or other absorbent material containing the composition of the metallic compound and being pulled through the equipment), train of “pigs” (in which the composition of the metallic compound, trapped between two or more “pigs”, is pushed by a compressed air system , for example), or any other means that allows the composition of the metallic compound to maintain contact with the desired parts of the surface to be treated. In this regard, the composition of the metallic compound can be liquid, and can also include a solvent. The optional solvent can be a hydrocarbon and mixtures thereof. In some embodiments, the solvent can be selected from carboxylic acids, toluene, xylene, benzene, alkanes, such as, for example, propane, butane, isobutane, hexane, heptane, octane and decane; alcohols, such as methanol, ethanol, n -propanol, isopropanol, n-butanol and isobutanol, mineral turpentine; βdicetones, such as acetylacetone; ketones like acetone; high paraffinic aromatic hydrocarbons; and combinations of two or more of these mentioned. Some modalities use solvents that do not contain water or water in trace amounts or greater, while other modalities use water as a solvent. In some embodiments, the metallic compound composition further comprises at least one carboxylic acid. Some modalities do not use solvents in the composition of the metallic compound. Other modalities do not use carboxylic acids in the composition of the metallic compound.

The composition of the metallic compound can be applied in some embodiments in which the composition has a temperature below about 250 ° C. This composition can also be applied to the substrate in additional embodiments at a temperature below about 50 ° C. In other embodiments, the liquid metallic compound composition is applied to the substrate at room temperature. In still other embodiments, this composition is applied at a temperature greater than about 250 ° C.

Following application, the at least one metal compound is at least partially converted to at least one metal oxide. In some embodiments, at least one metallic compound is fully converted to at least one metallic oxide.

Suitable environments for converting at least one metallic compound to at least one metal oxide include vacuum, partial vacuum, atmospheric pressure, high pressure equal to several high pressure environments equal to several hundred atmospheres, inert gases and reactive gases, as gases comprising oxygen, including pure oxygen, air, dry air, and oxygen mixtures in various proportions, with one or more other gases such as nitrogen, carbon dioxide, helium, neon and argon, as well as hydrogen, mixtures of hydrogen in various relationships with one or more other gases such as nitrogen, carbon dioxide, helium, neon and argon, as well as other gases, such as, for example, nitrogen, NH ₃ , hydrocarbons, H ₂ S, PH ₃ , each individually or in combination with various gases, and other gases that may or may not be inert in the conversion environment. In some embodiments, an environment suitable for converting at least one metallic compound to at least one metallic oxide is free or substantially free of oxygen.

The environment can be heated in relation to environmental conditions, in some modalities. In other embodiments, the environment may include reactive species that induce or catalyze the conversion of the metallic compound to the metal oxide, such as, for example, the acid-catalyzed hydrolysis of metal alkoxides. In still other modalities, the metallic compound is induced to convert to metal oxide by the use of induction heating, lasers, microwave emission, or plasma, as explained below.

The conversion environment can be accomplished in several ways. For example, a conventional oven can be used to bring the coated substrate to a temperature greater than approximately 250 ° C over a period of time. In some embodiments, the coated substrate environment is heated to a temperature above about 400 ° C, but less than about 450 ° C or less than about 500 ° C, for a selected period of time. In other embodiments, the coated substrate environment is heated to a temperature ranging from about 400 ° C to about 650 ° C. In additional embodiments, the room is heated to a temperature ranging from about 400 ° C to about 550 ° C. In even more embodiments, the environment is heated to a temperature ranging from about 550 ° C to about 650 ° C, from about 650 ° C to about 800 ° C, or from about 800 ° C to approximately 1000 ° C. In one embodiment, the room is heated to a temperature of up to about 425 ° C or 450 ° C. Depending on the size of the components and / or equipment, pipes, etc., the deadline can be extended until a sufficient conversion of a desired amount of the metallic compound to the metal oxides has been achieved.

In some applications, oxidation of the surface to be treated is not desired. In these cases, an inert atmosphere can be provided in the conversion environment to avoid such oxidation. In the case of heating the component in a conventional oven, a nitrogen or argon atmosphere can be used, among other inert gases, to prevent or reduce surface oxidation, before or during the conversion process.

The conversion environment can also be created using induction heating by means familiar to those skilled in the art of induction heating. Alternatively, the conversion environment can be made using a laser applied to the surface long enough to allow at least part of the metal compound to convert to metal oxides. In other applications, the conversion environment can be created using an infrared light source, which can reach temperatures sufficient to convert at least part of the metallic compounds to the metal oxides. Some embodiments may employ a microwave emission device to induce at least part of the metallic compound to be converted. Still other embodiments employ a plasma to provide the environment for converting the metallic compound to metallic oxide. In the case of induction heating, microwave heating, lasers, plasmas and other heating methods can produce the desired levels of heat levels in a short time, for example, within seconds, 1 minute, 10 minutes, 20 minutes , 30 minutes, 40 minutes, or an hour. Thus, in some modalities, the conversion environment can be created without the use of an inert gas environment, thus allowing the conversion to be done outdoors, outside a closed system due to the reduced time for undesirable compounds to develop in the surface of the material in the presence of ambient air.

The gas above the metallic compound on the surface can be heated, in some embodiments, to convert the metallic compound from the metallic oxide. Heating can be achieved by introducing gases at high process temperatures, which are fed through the assembled fluid transport or processing system, where the joints, welds, connections and one or more internal surfaces of the treatment system or fluid processing systems are coated with a thin protective film of the desired metal oxide (s). This high temperature gas can be produced by a conventional oven, induction heating coils, heat exchangers, industrial process ovens, exothermic reactions, microwave emission or another suitable heating method.

If there are elements of the process system and components or mounted surfaces on which it is not desired to have a nanocrystalline layer applied (for example, fluidized beds, catalytic surfaces, etc.), these can be temporarily bypassed using known methods of pipes, valves, ports , etc., during one or more steps of the method of the invention, either during the application of a composition on the internal surfaces or during the high temperature conversion phase, or a combination of the two. Likewise, areas that are to be kept free of the coating of the invention can be preserved with masks using methods known in the art before applying the composition of the method and converting it using any thermal or energy source.

In other applications, the composition of the metallic compound can be applied to the chosen areas of a component or system and an induction heating element can be passed very close to the area of interest to create the conversion environment. In some applications, the internal surface of a component may not be visible through the observation line, but an induction sensor kept very close to the internal or external surfaces of the component can allow sufficient heat to be developed on the wet surfaces being treated with metal compounds such that the desired oxides are formed by an indirect heating method. This technique may also be possible using infrared heating from the inside or outside of a component, flame heating, or other known methods of heating where the component material can be brought to the desired temperature to ensure conversion of the metallic compounds to the oxides. The use of this indirect heating method can also be used with a chosen atmosphere that can be supplied close to the wet surfaces of the tube or component, such as an inert atmosphere made of argon, as an example, which can serve to prevent the formation of oxides undesirable effects on the material surface to be treated.

In other applications, multiple layers may be desired such that additional protection of the material surface is provided. To reduce the time between applications of the coating of the invention, cooling methods can be used after each heating cycle to bring the surfaces to the required temperatures before subsequent applications of the metallic compounds. Such cooling methods can be used which are known in the art, such as spraying water, purging with cold steam through the interior of the system, evaporative cooling methods, and the like.

Representative compositions of coatings that have been found to be suitable in the embodiments of the present invention include, but are not limited to:

ZrO ₂ for example, from 0 to 90% by weight

CeO ₂ , for example, from 0 to 90% by weight

CeO ₂ -Zr) ₂ where CeO ₂ is about 10 to 90% by weight

Y ₂ O ₃ yttria stabilized zirconia where Y is about 1 to 50 mol%

TiO ₂ for example, from 0 to 90% by weight Fe ₂ O ₃ for example, from 0 to 90% by weight NiO for example, from 0 to 90% by weight AI ₂ O ₃ for example, from 0 to 90% in SiO ₂ y ₂ o ₃ weight

Cr ₂ O ₃

Mo ₂ O ₃

HfO ₂

La ₂ O ₃

Pr ₂ O ₃ Nd ₂ O ₃

Sm ₂ O ₃

I ₂ O ₃

Gd ₂ O ₃

Tb ₂ O ₃ Dy ₂ O ₃

Ho ₂ O ₃

Er ₂ O ₃

Tm ₂ O ₃

Yb ₂ O ₃

Lu ₂ O ₃

Mixtures of these compositions are also suitable for use in the invention.

Oxides of the following elements can also be used in embodiments of the present invention: lithium, beryllium, sodium, magnesium, aluminum, silicon, potassium, calcium, scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, germanium, arsenic, bromine, rubidium, strontium, yttrium, zirconium, niobium, molybdenum, technetium, ruthenium, rhodium, palladium, antimony, tellurium, silver, cadmium, indium, tin, barium cesium, lanthanum, cerium, praseodymium, neodymium , Promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, hafnium, tantalum, tungsten, rhenium, osmium, iridium, platinum, gold, mercury, thallium, lead, bismuth, radio, actinium , Thorium, Protactinium, Uranium, Neptunium, Plutonium, Americium, Curium, Berkelium, Californium, Einsteinium, Fermium, Mendelius, Nobelium, and Laurence. Oxides containing more than one of the preceding elements, and oxides containing elements in addition to the aforementioned elements, can also be used in embodiments of the present invention. For example, SrTiO ₃ and MgAI ₂ O ₄ are included. These materials are likely to form at least in small amounts when appropriate metallic compounds are used, depending on the conditions of the conversion process. In some embodiments, the molar ratio of metallic compounds deposited on the surface corresponds to a molar proportion of metallic oxides after conversion.

The invention relates, in some embodiments, to diffuse coatings and thin films (and articles thus coated), containing at least one rare earth metal oxide, and at least one transition metal oxide. As used here, “diffuse” means that metal oxide molecules, nanoparticles, nanocrystals, larger domains, or more than one of the preceding ones, have penetrated the substrate. The diffusion of metal oxides can vary in concentration from rare interstitial inclusions in the substrate, to the formation of materials that contain significant amounts of metal oxide. A thin film is understood to indicate a layer, no matter how thin, composed substantially of metal oxide. In some embodiments, a thin film has very little or no substrate material present, while in other embodiments, a thin film comprises atoms, molecules, nanoparticles, or larger domains of substrate ingredients. In some embodiments, it may be possible to distinguish between diffuse portions and thin films. In other embodiments, there may be a gradient in which it is difficult to see a boundary between the diffuse layer and the thin film. In addition, some modalities may have only a diffuse layer and a thin film. Still other modalities include thin films in which one or more species have migrated from the substrate to the thin film. The terms "metal oxide layer" and "surface comprises at least one metal oxide" include all possibilities, including diffuse coatings, thin films, stacked thin films, and combinations thereof.

As explained here, the diffuse coating of some embodiments of the invention provides greater performance, in part, because it penetrates the surface of the coated substrate to a depth providing good anchorage for the material being coated, without the need for intermediate bonding layers. In some embodiments, the diffuse layer penetrates the substrate to a depth of less than about 100 Angstrons. In other embodiments, the diffuse layer penetrates from about 100 Angstrons to about 200 Angstrons, from about 200 Angstrons to about 400 Angstrons, from approximately 400 Angstrons to about 600 Angstrons, and more than about 600 Angstrons and, in some modalities from about 200 Angstrons to about 600 Angstrons. This diffuse coating allows for much thinner films [in some embodiments about 0.1-1 micron thick (or about 0.5 microns, when about 6 layers are used)] to be applied, and can still provide equivalent protection to that provided by conventional coating or thin film technologies. This, in turn, allows for thinner films or coatings to be established, significantly reducing the cost of materials inherent to the substrate. Thus, some embodiments of the present invention provide a thin film with a thickness of about 5 nm. Other modalities provide a thin film about 10 nm thick. Still other embodiments provide a thin film about 20 nm thick. Still other embodiments provide a thin film about 100 nm thick. Other modalities provide a thin film with a thickness of less than about 25 microns. Still other embodiments provide a thin film less than about 20 microns thick. Still other embodiments provide a thin film less than about 10 microns thick. However, other embodiments provide a thin film less than about 5 microns thick. Some modalities provide a thin film with a thickness of less than about 2.5 microns. Even other modalities provide a thin film less than 1 micron thick.

In some embodiments of the invention, the metal oxide coating may contain other species, such as, for example, species that have migrated from the substrate to the metal oxide coating. In other embodiments, the other species may come from the environment in which at least one metallic compound is converted. For example, conversion can be carried out in an environment in which other species are supplied through known vapor deposition methods. Still other embodiments provide other species present within or derived from the metallic compound, at least one or composition comprising the compound. Suitable other species include metal atoms, metal compounds including metal atoms, such as oxides, carbides, nitrides, sulfides, phosphides, and mixtures thereof, and so on. The inclusion of other species can be accomplished by controlling conditions during conversion, such as using a selected environment during the heat conversion process, for example, a partial vacuum or an atmosphere containing O ₂ , N ₂ , NH ₃ , one or more hydrocarbons, H ₂ S, alkylthiols, PH ₃ , or a combination thereof.

Some embodiments of the present invention provide metal oxide coatings that are substantially free from other species. For example, small amounts of carbides can form along side oxides when, for example, metal carboxylates are converted, if special measures are not taken to remove carbon from the carboxylate binders. Thus, the conversion of metallic compounds in the presence of oxygen gas, air or oxygen mixed with other gases, reduces or eliminates the formation of carbide in some embodiments of the present invention. In addition, the rapid heating of the conversion environment, for example, with induction heating, microwave heating, lasers, plasmas and other heating methods that can produce the necessary heat levels in a short time, reduces or eliminates the formation of other species, in other modalities. At least one rapid heating technique is used in combination with an oxygen-containing atmosphere in yet other embodiments.

Additional modalities employ several heating steps to reduce or eliminate the formation of other species. For example, the formation of carbide can be reduced during the formation of metal oxide in some modalities of applying a metal precursor composition containing a metallic carboxylate compound to a surface, subjecting the surface to low temperature cooking at about 250 ° C under vacuum by introducing air and maintaining the temperature, and then increasing the temperature to about 420 ° C under vacuum or inert atmosphere to convert the metal carboxylate to the metal oxide. Without wishing to be bound by theory, it is believed that low-temperature cooking removes most, if not all, of the binder, resulting in an oxide film substantially free of metal carbide.

Still other modalities employ more than one layer to reach at least one layer substantially, without other species. For example, in some embodiments, a base layer of at least one metal oxide is formed by at least one metal carboxylate under an inert atmosphere. Such a base layer may contain metal carbides, due to the initial presence of the carboxylate binders. In addition, as a base layer they can exhibit good adhesion and resistance, for example, when the surface is composed of a carbon steel alloy. Then, one or more subsequent metallic compounds are repeatedly applied and converted into an oxygen-containing atmosphere, for example, and the subsequent layers of the metal oxide form substantially without metal carbides. In some embodiments, six or more layers are formed in the base layer.

In addition, the effect of any inadequacies in physics, chemistry or crystallographic properties (particularly with respect to differences in thermal expansion coefficients) can be minimized by the use of very thin coating materials and the resulting films. In addition, the structure of the film's small crystallites (3-6 nanometers, in some embodiments) increases the Hall-Petc.h strength in the film structure significantly.

In some embodiments, the present invention provides methods of reducing the differences in the thermal expansion coefficients between a substrate and a metal oxide coating proximal to the substrate. In some modalities, the methods of reducing the differences in the thermal expansion coefficients between a substrate and at least one metal oxide make up the interposition of a diffuse layer between the substrate and the metal oxide. Interposition This coating comprises spreading at least one metallic compound to the substrate and then at least partially converting the metallic compound from at least one of at least one metal oxide.

The thermal stability of the metal oxide coating can be tested, in some modalities, by exposing the coated material to thermal shock. For example, a surface with a metal oxide coating can be observed, as by microscopy. Then, the surface may be exposed to a thermal shock, such as by rapid heating or rapid cooling. Rapid cooling can be induced by, for example, immersing the surface at room temperature or at higher temperatures into liquid nitrogen, keeping the surface under liquid nitrogen for a while, and then removing the surface from liquid nitrogen. The surface is then observed again, looking for signs of delamination, cracks, or other degradation of the coating due to thermal shock. The thermal shock test can be repeated to see how many shock cycles of a given metal oxide coating can withstand before observing the possible existence of a certain degree of degradation. Thus, in some embodiments of the present invention, the at least one metal oxide coating resists at least five, at least ten, at least twenty-five, at least fifty, or at least one hundred cycles of thermal shock from room temperature down to the temperature of liquid nitrogen.

The nanocrystalline grains resulting from some embodiments of the methods of the present invention have an average size or diameter of less than about 50 nm. In some embodiments, nanocrystalline metal oxide grains have an average size ranging from about 1 nm to 40 nm or about 5 nm to 30 nm. In another embodiment, nanocrystalline grains have an average size ranging from about 10 nm to 25 nm. In additional embodiments, nanocrystalline grains have an average size of less than about 10 nm or less than about 5 nm.

In other embodiments, the invention relates to metal oxide coatings (either film, diffused thin, or both diffuse and thin films) and articles comprising such coatings, where the coatings contain two or more rare earth metal oxides and at least a transition of metal oxides. Other embodiments of the invention relate to metal oxide coatings (or objects containing them), containing ceria, a second rare earth metal oxide, and a transition metal oxide. Some modalities refer to coatings of metallic oxide (or objects that contain them), containing yttrium, zirconium, and a second rare earth metal oxide. In some cases, the second rare earth metal oxide may include platinum or other known catalyst elements.

In some embodiments, the metallic compound applied to the surface comprises a cerium compound, and the metal oxide coating comprises cerium (or ceria) oxide. In other embodiments, the metallic compound applied to the surface comprises a zirconium compound, and the metal oxide coating comprises zirconia. In still other embodiments, a solution comprising both a cerium compound and a zirconium compound is applied, and the resulting metal oxide coating comprises ceria and zirconia. In some cases, the zirconia formed by the process of the invention comprises crystal grains with an average dimension of about 3-9 nm, and the ceria formed by the process of the invention comprises crystal grains with an average dimension of about 9-18 nm . Nanostructured zirconia can be stabilized in some modalities with yttria or any other kind of stabilization alone or in combination. In still other embodiments, the metal oxide coating comprises zirconia, yttria or alumina, each alone or in combination with one or both of the others.

In additional embodiments, the method of the invention further includes a step of applying an organosiloxane silicone composition over the formed oxide coating and exposing the coated substrate to an environment that will remove volatile components from the composition, without decomposing organo-silicon bonds. In addition, other treatments can be performed after the formation of an oxide layer. As explained here, additional metal oxide coatings, which can be the same or different, can be added. In some embodiments, the metal oxide (s) can be etched and polished, carburized, nitrided, painted, powder coated, plated, or anodized. In some embodiments, the at least one metal oxide serves as an adhesive layer in at least one additional layer. Such additional coatings need not be formed in accordance with the present invention. Some embodiments offer a metal oxide bonding coating that allows for an additional coating that may not adhere to the surface in the absence of the bonding layer. In addition, the substrate can be subjected to heat treatment, before or after a metal oxide coating is formed on the substrate. For example, a substrate having a metal oxide coating in accordance with the present invention can be annealed at high temperatures to reinforce the substrate. In another example, a substrate can be kept close to absolute zero, either before or after a metal oxide coating is formed on the substrate. Adequate heat treatment temperatures range from about OK to several thousand K, and include temperatures of liquid hydrogen, helium, liquid neon, liquid argon, liquid krypton, liquid xenon, liquid radon, liquid nitrogen, liquid oxygen, liquefied air and dry ice, and temperatures obtained by mixtures, azeotropes and vapors of these and other materials.

The methods of the present invention can be used during or after the manufacture of a particular component of a processing or fluid transport system. For example, one or more layers of oxide can be applied to a section of pipe as it is being manufactured, or after the pipe is assembled in a fluid processing or transport system. In addition, in some embodiments, the methods of the present invention can be incorporated into conventional manufacturing steps. For example, after tubes are welded, they are often subjected to heat treatment to relieve the stresses introduced by the welding process. In some embodiments of the present invention, at least one metallic compound is applied after welding and before this heat treatment. In these modalities, a heat treatment converts at least one metallic compound into at least one metallic oxide and relieves the stresses arising from the weld.

The process of the invention can allow the use of coatings on a wide variety of materials, including the application of CeO ₂ and ZrO ₂ coatings for ceramic materials and / or solid metals previously not possible to be coated with these materials. Some embodiments of the present invention provide a relatively low temperature process, which do not harm or distort many substrates, do not produce toxic or corrosive aqueous materials, and can be applied on-site or "in the field" without purchasing expensive equipment.

In addition, the nature of the interstitial boundaries resulting from nanocrystalline structures of the invention in various modalities may consist of selected ingredients in order to increase ionic conductivity, while decreasing electronic conductivity, or may be composed of selected ingredients in order to increase conductivity. mixed material, or modify its porosity. Similarly, many other properties can be changed through the careful selection of diverse ingredients, which are formulated, as part of the metallic compound composition of the invention.

In some embodiments of the present invention, a substrate comprising at least a part of a component's structure is placed inside a vacuum chamber and the chamber is evacuated. Optionally, the substrate can be heated or cooled, for example, with gases introduced into the chamber or by a heat transfer fluid that flows through the structure of the mounting substrate. If a gas is introduced, care must be taken that it will not alter the substrate in an unintended manner, such as by oxidizing a hot surface containing iron by a gas containing oxygen. The optionally introduced gas can be evacuated once the substrate reaches the desired temperature. Vapor from one or more metal compounds, such as cerium 2-hexanoate (III), enters the vacuum chamber and settles on the substrate. A specific volume of a fluid composition containing the metallic compound can provide a specific amount of compounds for the surface of the substrate inside the vacuum chamber, depending on the size of the chamber and other factors. Optionally, a selected gas is vented into the chamber and fills the vacuum chamber to a chosen pressure, in one example, equal to an atmosphere. The chamber is heated to a temperature sufficient to convert at least part of the compound to oxides, for example, 450 ° C, for a specified amount of time sufficient for the conversion process, for example, 30 minutes. In this example, a layer of cerium oxide is formed on the substrate. Optionally, the process can be repeated as many times as desired, forming a thicker layer of cerium oxide on the substrate. In some embodiments, the component can be cooled in relation to room temperature, such as, for example, the temperature of liquid nitrogen, to assist the deposition process. In other embodiments, a reducing atmosphere can be used to convert at least part of the metal oxides to the metal.

In other embodiments, the substrate can include one or more polymers, such as polyvinyl chloride. The polymer substrate can be kept at lower enough temperatures to avoid degradation of the substrate during the heating process, for example, the temperature of liquid nitrogen, while the metallic compound converts to the oxide due to any technique that heats the metallic compound, but not the substrate to a significant degree. Examples of heating techniques, such as flash lamps, lasers, and microwave heating. In addition, materials that degrade on exposure to high temperatures can be kept at lower temperatures using the same techniques. For example, glass, low temperature fusion metals, polycarbonate * ducks, and similar substrates can be kept at low temperatures as long as at least one metallic compound is converted to at least one metallic oxide.

When used in this document in reference to the process gases used to carry out the process of the invention, the term "high temperature" means a temperature high enough to convert the metal compound to metal oxide, generally in the range of about 200 ° C to about 1000 ° C, such as from about 200 ° C to about 400 ° C, or from about 400 ° C to about 500 ° C, from about 500 ° C to 650 ° C, about 650 ° C to about 800 ° C, or from about 800 ° C to approximately 1000 ° C. Process gases at even higher temperatures can be used, so that when the gas is passed through the Process gases at even higher temperatures can be used, so that when the gas is passed through the transport system or from fluid processing during the process of some embodiments of the invention, the temperature of the gas leaving the system falls within the range given above.

A given embodiment of the invention described herein may involve one or more of the various basic concepts. For example, a concept refers to a surface treatment, which generally meets the technical properties described above and can be manufactured at low cost. Another concept concerns a method for forming a protective oxide film on the surface of a metal. Another concept refers to a two-step process adapted to form a prophylactic layer on the internal surfaces of a fluid transport or processing system. Another concept refers to the creation of thin films of nanocrystalline zirconia on surfaces to resist fibrous growth of carbon and other elements. Another concept is related to a means to apply a protective coating to a set of various components through a process to heat a closed system as a curing method for the coating.

In some embodiments of the invention, an oxidizing coating can be formed on a substrate by applying a liquid metallic compound composition to the substrate through a process of dipping, spraying, vapor deposition, scraping, brushing, or any other known means of application from a liquid to an internal surface of a conduit, or process equipment. This liquid metallic compound composition comprises at least one rare earth metal salt of a carboxylic acid and at least one transition metal salt of a carboxylic acid, in a solvent, in some embodiments. The surface, once wetted with the composition, is then exposed to a heated environment that will convert at least part of the metal compounds to metal oxides, forming an oxidizing coating on the substrate.

The metal oxide coatings resulting from the conversion process, such as thin films of nanocrystalline materials, are applied to material substrates to form one or more thin layers of protection. Other applications of the metallic compounds, following exposure to ambient conversion (for example, heating the surface using the means described above) can be made to create multiple layers of thin oxide films stacked on top of each other.

The process can be used to create a structure that comprises a nanocrystalline containing oxygen molecule for the chosen applications. Alternatively, the resulting nanocrystalline structure can comprise a metallic compound containing a metal, ceramic, or a 'cermet'.

A benefit for some embodiments of the invention is the ability to apply the metallic compound composition to an assembled system and then to release high temperature gases through the system to achieve the conversion process, resulting in a well-dispersed layer of metal oxide on all internal surfaces. This is especially beneficial for welded pipe systems, heat exchangers, and similar components that use welding for their assemblies, said welding typically destroying any surface treatments applied to pipes, heat exchangers or other parts before welding. The high temperature conditions of the welding process tend to destroy all protective coatings. The invention provides a way to create a final metal oxide coating covering all parts of the process system, creating a protective layer for welded joints and also for internal components.

To create a thin, less porous film, for some embodiments, the material can be added to the base fluid to act as the filler material. In this way, the porosity of the finished coating is changed with the inclusion of selected nanoparticles elements in the liquid composition of the metallic compound before exposure to an environment that will convert at least a portion of the metallic compound (s) into metal oxides. The result is a thinner, denser film.

In some applications, where it is desirable to reduce a metal oxide to a pure metal, the treated substrate can be exposed to a reducing agent, such as hydrogen or another known reducing agent, through known means for reducing oxide. For example, 7% hydrogen in argon heated to 350 ° C can be used to form platinum in certain embodiments. Other metals that may be desired, such as for catalytic purposes, for example, include but are not limited to platinum, palladium, rhodium, nickel, gold, cerium, silver, zinc, lead, ruthenium rhenium, and combinations of two or more of the same .

As described above, the method of the invention can be used to provide prophylactic coatings for internal surfaces of transport or fluid processing systems, and is of particular use in the field of transport or fluid processing systems in the oil and gas industries. natural, where carbon encrustation, corrosion and hydrogen embrittlement are particular problems in piping and processing equipment. For example, coating with yttria-stabilized ceria or zirconia, or a combination of ceria and zirconia will significantly reduce carbon fouling on steel surfaces exposed to oil and other hydrocarbons at temperatures of around 570 ° C, with effect of protection against any effective or measurable carbon deposition. Uncoated steel surfaces exposed to similar conditions become sufficiently soiled with carbon to require cleaning after about 18 months of service. Inhibition of carbon scale occurs during exposure to oil or other hydrocarbons at temperatures as high as 900 ° C. Similar improvement in fouling will occur in fluid processing systems used to process natural gas.

In addition to protection against carbon scale, the method of the invention provides protection against scale and other corrosion problems frequently encountered in chemical or hydrocarbon processing operations in various modalities. For example, the method of the invention provides a partial or total barrier against the intrusion of hydrogen into a metal substrate, reducing the surface of the substrate and degradation by means of this known mechanism, in some embodiments. In particular, the method of the invention provides an effective barrier against corrosive attack in later embodiments. Because the resulting surface coating provides an effective barrier between the material of process equipment (usually metal, such as iron or steel) and the environment (for example, crude oil, cracked hydrocarbons, or natural gas flow), and others Electrochemical reactions between the metal and the process flow are effectively reduced or prevented in yet other modalities. This is particularly important for stainless steel piping systems, where the high temperatures involved in steel welding induce chromium (the main passivation element in stainless steel) to migrate to the grain boundaries, creating a galvanic coupling between areas of high Cr and low Cr areas, which can lead to corrosive attack. As the method of the invention allows the application of the coating after the weld has been formed (and any high temperature damage has occurred) in some embodiments, the areas of the system adjacent to the weld are isolated from exposure to the potentially corrosive environment of the fluid being processed .

Exposure to certain types of welding, galvanic corrosion, and most importantly to hydrogen sulfide (often found in petroleum and natural gas process currents) can introduce hydrogen into the crystalline structure of metal process equipment, leading to embrittlement and cracking. The method of the invention, by preventing exposure of the metals to any hydrogen sulfide or hydrogen contained in the process flow, can reduce or eliminate this form of attack in certain embodiments of the present invention.

Other systems can also be protected against various forms of encrustation. Heat exchangers that can be protected according to various embodiments of the present invention include any type of heat exchanger. Known heat exchangers transfer thermal energy, either for heating and cooling purposes, for example, between gases, between gas and a liquid, between a liquid and a solid, and between a gas and a solid. Heat exchangers for two-phase, semi-solid, slurry and sludge systems are also known. Heat exchangers include, for example, oil heating units in refineries, cooling towers, automotive radiators, HVAC systems such as air conditioners, solar power towers, geothermal harvesters, cooling units, and so on. .

Materials that can be protected against fouling in accordance with the present invention include any material that can receive a protective metal oxide coating. Such materials include, for example, metals, ceramic materials, glass and cermets, as well as compounds and polymers that can withstand the conditions of the process of converting metallic carboxylate to metallic oxide. Metals that can be protected include, but are not limited to, substantially pure metals, alloys and steels, such as, for example, low alloy steels, carbon steels, stainless steel, 300 series stainless steel, 400 series stainless steel, nickel-based alloys, high chromium steels, and high molybdenum steels.

Industrial and commercial products that can be protected according to the present invention are not limited. Oil refinery; petrochemical processing; transport and storage of oil, such as pipelines, oil tankers, fuel transport vehicles and fuel gas tanks and pump station, sensors, manufacturing of industrial chemicals, storage and transportation, automotive fluid systems, including fuel systems, lubrication systems, radiators, air heaters and coolers, braking systems, and breakage, power steering, transmissions, hydraulic systems and similar systems; aeronautical and aerospace fluid storage and transport systems including fuel systems and hydraulic systems; and food and dairy process systems; combustion engines, turbine engines, and rocket engines; among many others, can benefit from the present invention.

EXAMPLES

Example 1

Five 5.08 cm x 5.08 cm (2 "x 2") coupons in finished SS304 steel (McMaster-Carr) were individually designated "uncoated", "zirconia", "glass", YSZ ", and" clay". These compositions imitate chemically and thermally inert materials by the same names known in nature and industry, in an inventive way. A wide range of similar materials may suggest additional compositions for use with the modalities of the present invention. The “uncoated” coupon was not given any coating to function as a control. Each of the other coupons was coated on one side, with the following compositions according to the modalities of the present invention:

Zircon: zirconium 2-ethylexanoate (Weight 28% w of the final composition, Alfa Aesar), silicon silicon 2-ethylexanoate (33.5% by weight, Alfa Aesar) and chromium 2-ethylexanoate (1% w, Alfa Aesar ) were mixed in 2-ethylexanoic acid (weight 37.5% w, Alfa-Aesar), and the composition was coated by rotation over the surface of the steel substrate.

Glass: silicon 2-ethylexanoate (Weight 74% w, Alfa Aesar), sodium 2-ethylexanoate (5.2% w, Alfa Aesar), calcium 2-ethylexanoate (11% w, Alfa Aesar) and 2-ethylexanoate chromium (1.4% by weight, Alfa Aesar) were mixed in 2-ethylexanoic acid (8.4% w, Alfa Aesar), and the composition was coated by rotation over the surface of the steel substrate.

YSZ: Yttrium 2-ethylexanoate powder (2.4% w, Alfa Aesar) was dissolved in 2-ethylexanoic acid with stirring at 75-80 ° C for one hour (60% w, Alfa Aesar). Once the composition has cooled to room temperature, zirconium 2-ethylexanoate (36.6% by weight, Alfa Aesar) and chromium 2-ethylexanoate (1% w, Alfa Aesar) were mixed. The composition was coated by rotation over the surface of the steel substrate.

Clay: Aluminum 2-ethylexanoate (15% w, Alfa Aesar), silicon 2-ethylexanoate (45% w, Alfa Aesar) and chromium 2-ethylexanoate (2% by weight, Alfa Aesar) were mixed in 2- ethylexanoic. This composition was manually rubbed onto the substrate surface due to the viscosity of the composition. The composition apparently reacted with moisture in the air and began to solidify, making application difficult.

The coated steel coupons were placed in a vacuum oven and evacuated to about 20-60 millitorr. The coupons were heated to 450 ° C, and then left to cool to room temperature. The deposit and heating process was repeated to apply eight coatings of the appropriate composition to each coupon.

Each coated coupon was mounted in a test cell with a glass cylinder (2.54 cm (Tj internal diameter x 2.86 cm (1.125 ”) attached to the coated part of the coupon. A rubber seal formed a seal between the glass cylinder and coupon. Aqua Regia was prepared from HNO ₃ (1 part, vol., 70% stock, # 33260, Alfa Aesar) and HCI (3 parts, vol., Stock -37%, # 33257, Alpha Aesar), poured into a glass cylinder, and allowed to contact the coupon for an hour, then the coupon was removed, washed and photographed. The photos of the tested coupons appear in Figures 3-7.

Aqua Regia, so called because it is known to dissolve noble metals like gold and platinum, chemically etched the uncoated stainless steel coupon quite chemically. See Figure 3. The zircon coupon, in contrast, remains largely showing only small dots. See Figure 4. The glass coupon also remains largely unattached, showing concealed scratch-like features. See Figure 5. The YSZ coupon shows a significant attack. See Figure 6. The Clay coupon also shows the attack, although less severe than that of the uncoated coupon. See Figure 7.

On a scale of 0 to 10, with 0 representing severe corrosion and 10 representing complete protection, the coatings showed the following performances:

Coupon Performance Uncoated 0 Zircon 8 glass 7-8 YSZ 0-1 Clay 0-1

The observation of the zircon and glass coupons in magnifications from 100x to 1000x before exposure to Aqua Regia revealed uniform coatings, mainly amorphous. The observation of the YSZ coupon in these extensions even revealed a surface coating with a crystalline structure. The observation of the clay coupon revealed uneven coverage, probably due to the reaction catalyzed by moisture and premature solidification. The preparation and application of the clay composition in a moisture and / or oxygen-free environment can improve the characteristics and performance of the coating.

These results demonstrate protection of a steel substrate in a highly corrosive environment by coatings designed in accordance with the present invention. These results also demonstrate simple experiments to test metal oxide coatings to assess how they could perform in a given environment.

Similar experiments can be done in other environments to determine how metal oxide coatings can perform in those environments. Those usually versed in the technique will recognize that compositions that have not performed well against Aqua Regia can perform well in other environments. For example, the YSZ layer is believed to reduce or prevent the accumulation of coke. In addition, the performance of a composition depends, in part, on the conditions of application and conversion. For example, the clay composition is expected to perform well if applied and converted into a suitable environment, as discussed above.

Example 2

Figure 8 shows a TEM micrograph in magnification of approximately two million x of an SS304 stainless steel substrate (104) with eight layers of an yttria / zirconia composition (102). The figure illustrates a diffuse layer, labeled oxide-substrate intercalation (106). In this example, the diffused coating is about 10 nm thick. TEM also shows crystalline planes, indicating the nanocrystalline nature of yttria / zirconia.

Example 3

The internal oil-contact surfaces of a boiler for a fractionated petroleum distillation column are cleaned and then wetted with a well stirred composition containing cerium 2-ethylexanoate (lll) (203 g; all weights are per kilogram of final composition), chromium acetylacetonate (III) (10.1 g) and cerium (IV) oxide nanoparticles (10.0 g, 10-20 nm, Aldrich) in 2-ethylexanoic acid (777 g). The composition is applied to the boiler tubes by inserting a “pig” into the first boiler tube, adding an aliquot of the composition to the tube, and placing a second “pig” such that the first “pig” and the second “pig” substantially contain the rate. Then, compressed nitrogen is introduced behind the second “pig” and the pressure is increased above 1 atm, until the scraping package moves. The pressure is kept constant until the scraping package appears on the other side of the boiler, and the inner surface of the tube is wet with the composition. Steam at 500 ° C heats the boiler in the usual way for 30 minutes and then the boiler is left to cool. A coating of substantially non-porous chromium oxide stabilized by chromium oxide forms on the surfaces of the boiler that contact the oil.

Example 4

Under an atmosphere of nitrogen saturated in ethanol, surfaces that contact milk from a treat pasteurizer are wetted with a well stirred composition containing (IV) titanium (IV) ethoxide in ethanol (500 g, 20% Ti, Aldrich) and dry ethanol ( 500 g), using a “pig”, as shown in Figure 1. After the “pig” is removed from the pasteurizer, dry nitrogen heated to 450 ° C purges through the pasteurizer for fifteen minutes, and the pasteurizer is left to cool under nitrogen flow to room temperature. The analysis will reveal a layer of titanium dioxide on the surfaces of the pasteurizer that have contact with the milk.

Example 5

A clean automobile exhaust collector is immersed in an agitated bath containing a first composition containing 2,2,6,6-tetramethyl-3,5 zirconium (IV) heptanedionate (459 g), and 2,2, Yttrium 6,6-tetramethyl-3,5-heptanedionate (ll) (72.9 g), and hexanes (1 kg) such that the composition contacts the internal and external surfaces. Optionally, the openings can be closed so that the first composition does not contact the internal surfaces. The collector is removed from the composition, suspended, and rotated to allow excess composition to fall into the bath. Microwave radiation radiates the external surfaces for ten minutes, and the zirconia stabilized by yttrium coating forms on the outside of the collector. The collector exhaust contact surfaces are purged with a second composition containing 2,2,6,6-tetramethyl-3,5 zirconium (IV) heptanedionate (459 g), 2,2,6,6-tetramethyl-3 , Yttrium (III) 5-heptanedionate (72.9 g), platinum (ll) acetylacetonate (1.01 g) and hexanes (1 kg), and the composition is drained from the collector. Argon gas heated to 450 ° C is transmitted through the interior of the collector for 30 minutes. Then, the argon gas containing 7% hydrogen heated to 350 ° C passes through the interior of the collector for 30 minutes. A yttria-stabilized zirconia coating will form on the inner surface of the collector. The internal surface will also contain metallic platinum sites to catalyze the oxidation of partially burned hydrocarbon fuel. In addition, a yttria stabilized zirconia coating will form to protect the collector exterior from corrosion. Optionally, the dispenser can be cooled to room temperature and then slowly lowered into a nitrogen bath for some time.

Example 6

The inner surfaces of the tubes of a stripped coqueador were cleaned and coated as follows. A mechanical “pig” was passed through the tubes, driven by water, to scrape carbon residues from the inner parts of the tubes. An air compressor equipped with an air dryer blows dry air through the wet tubes overnight at a pressure of 1,034 kPa (150 psi) and a volume of about 4.5 m ³ (160 cubic feet) standard per minute. Then, nitrogen gas was introduced into the pipes and the coker was heated gradually to s coker, it was gradually heated to 398.9 ° C426.7 ° C (750-800 ° F) to further dry the tubes, and then gradually left to cool.

Sponges of approximately 1 kg of open cell polyethylene having a cell polyethylene diameter of two kilograms open sponges with a diameter of 21.6 cm to 35.6 cm (8.5 ”to 14”) were squeezed by hand ( with protective glove) and immersed in a composition comprising zirconium (IV) 2-ethylexanoate (85 mol%) and cerium (III) 2-ethylexanoate (15 mol%), and allowed to absorb the composition. Based on the estimate that one liter of the composition covers approximately 200 m ² of the inner surface of the tube, the volume of the compound was measured before and after contact of the sponge with the composition. An embedded sponge was then introduced into a 7.62 cm (3 ") diameter pig launcher, which was connected by a flange to the tubes to be treated on the effluent side of the process. The tubes to be treated contained diameters ranging from 7.62 cm (3 ") to 10.16 cm (4"), and also included "mule ears", 90 ° insertions of one tube entering another. Mule ears provide a particular challenge to certain rigid-bodied pigs, making some systems very difficult for a pig to pass along its length. At the opposite end of the tube (inlet to the process), a receiver “pigs” launcher was attached, and a hose was arranged to pass any fluid effluent (gas and / or liquid) through and ventilated water separator into the atmosphere. The pig launcher with the soaked sponge was sealed, and compressed air from a compressor capable of 4.5 m ³ to 45.30 m ³ (160 to 1600 ft ³ ) and pressure of 413.7 kPa (60 psi) at 1,034 kPa (160 psi) of pressure it took the sponge soaked from the “pig” launcher, through the tubes, and into the “pig” receiving launcher at a speed ranging from 6.10 m / s (20 ft / s ) at 38.10 m / s (125 ft / s). After the sponge was recovered, the tube was sealed and purged with nitrogen gas. The coking burners were fired one by one as usual for the coking to prevent the tubes from heating up too quickly, at a maximum heating rate of 121.1 ° C / ha (250 ° F / h) to about 437.8 ° C / h (850 ° F / h) up to a maximum temperature of 593.4 ° C (1100 ° F). Then, the burners were turned off one by one to slowly cool the mixer in order to again protect the pipes in the usual way. When the cooling tubes dropped to 121.1 ° C (250 ° F), another sponge soaked with the coating composition was passed through the tubes in the same way, followed by a nitrogen purge, heating and cooling. Each recovered sponge was observed for moisture, damage and cleanliness, indicating the tubing was being thoroughly wetted and cleaned thoroughly as the sponge passed through it.

As stated earlier, the detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the modalities presented are merely representative of the invention and can be materialized in several forms. It will be appreciated that many modifications and other variations that will be perceived by those of ordinary skill in the art are within the scope of the present invention in accordance with the claims presented below, without departing from the orientations, spirit and scope intended for the invention. In addition, the description presented of the different modalities does not necessarily imply exclusion. For example, "some" modalities may include all or part of "another" and "other more" modalities within the scope of that invention. Additionally, "one" can mean "one and more than one", it does not mean "one and only one" in the sense of excluding duplicate items or additional items.

Claims (30)

1. Method for cleaning the inner surface of a pipe, FEATURED by the fact that it comprises: place a first “pig” as close to the inner surface of the tube, where the first “pig” is a compressible sponge with a diameter in an uncompressed state of at least about 1.4 times the largest inner diameter of the tube; applying a first cleaning composition to the internal surface with the first "pig", thereby cleaning the internal surface, where the first cleaning composition comprises a carboxylic acid; and substantially removing the first cleaning composition from the inner surface. 2. Method according to claim 1, CHARACTERIZED by the fact that the compressible sponge is spherical in an uncompressed state. 3. Method according to claim 1, CHARACTERIZED by the fact that the compressible sponge has a diameter in an uncompressed state of at least about 2 times the largest internal diameter of the tube. 4. Method according to claim 3, CHARACTERIZED by the fact that the compressible sponge has a diameter in an uncompressed state of at least about 3.5 times the largest internal diameter of the tube. 5. Method according to claim 1, CHARACTERIZED by the fact that the first cleaning composition comprises acetic acid, formic acid, propionic acid, 2-ethylexanoic acid, or a combination of two or more of those mentioned. 6. Method according to claim 5, CHARACTERIZED by the fact that the first cleaning composition consists essentially of 2-ethylexanoic acid. 7. Method according to claim 1, CHARACTERIZED by the fact that substantially removing the first cleaning composition comprises heating the internal environment of the tube. 8. Method, according to claim 7, CHARACTERIZED by the fact that the heating is carried out in the presence of nitrogen, and in the substantial absence of oxygen. 9. Method according to claim 7, CHARACTERIZED by the fact that the heating is at a temperature of about 400 ° C to 427 ° C. 10. Method, according to claim 1, CHARACTERIZED by the fact that it additionally comprises: before substantially removing the first cleaning composition, place a second “pig” as close to the inner surface of the tube; and apply a second cleaning composition to the inner surface with the second “pig”. where substantial removal of the first cleaning composition also substantially removes the second cleaning composition. 11. Method according to claim 10, CHARACTERIZED by the fact that the second “pig” is a compressible sponge with a diameter in an uncompressed state of at least about 1.4 times the largest internal diameter of the tube. 12. Method according to claim 10, CHARACTERIZED by the fact that the second cleaning composition is the same as the first cleaning composition. 13. Method for the formation of at least one metal oxide on an internal surface of a system for processing or transporting an industrial fluid or its component, CHARACTERIZED by the fact that it comprises: place at least one first “pig” as close to the internal surface of the processing or transport system as an industrial fluid or a component thereof; apply at least one cleaning composition to the internal surface with at least one first “pig”; substantially removing at least one cleaning composition from the inner surface; place at least one second “pig” as close to the internal surface of the processing or transport system of the industrial fluid or a component thereof; apply at least one metallic compound on the internal surface with at least one second “pig”; and converting at least part of the at least one metallic compound to at least one metal oxide. 14. Method according to claim 13, CHARACTERIZED by the fact that the at least one first “pig” is a single compressible sponge that has, in an uncompressed state, a spherical shape and a diameter of at least about 1 , 4 times the largest internal diameter of the tube. 15. Method, according to claim 14, CHARACTERIZED by the fact that the compressible sponge has a diameter in an uncompressed state of at least about 2 times the largest internal diameter of the tube. 16. Method according to claim 15, CHARACTERIZED by the fact that the compressible sponge has a diameter in an uncompressed state of at least about 3.5 times the largest internal diameter of the tube. 17. Method according to claim 13, CHARACTERIZED by the fact that the at least one cleaning composition comprises a carboxylic acid. 18. Method according to claim 17, CHARACTERIZED by the fact that the at least one cleaning composition comprises acetic acid, formic acid, propionic acid, 2-ethylexanoic acid, or a combination of two or more of those mentioned. 19. Method according to claim 18, CHARACTERIZED by the fact that the at least one cleaning composition consists essentially of 2-ethylexanoic acid. 20. Method according to claim 13, CHARACTERIZED in that substantially removing at least one cleaning composition comprises heating the internal environment of the tube. 21. Method, according to claim 20, CHARACTERIZED by the fact that the heating is carried out in the presence of nitrogen, and in the substantial absence of oxygen. 22. Method according to claim 20, CHARACTERIZED by the fact that the heating is at a temperature of about 400 ° C to about 427 ° C. 23. Method according to claim 13, CHARACTERIZED by the fact that the at least one metal oxide comprises at least two rare earth metal oxides. 24. Method according to claim 13, CHARACTERIZED by the fact that the at least one metal oxide comprises ceria. 25. Method according to claim 13, CHARACTERIZED by the fact that the at least one metal oxide comprises yttria and zirconia. 26. Method, according to claim 13, CHARACTERIZED by the fact that the at least one metal oxide comprises ceria and zirconia. 27. Method according to claim 13, CHARACTERIZED by the fact that the at least one metal oxide comprises yttria, zirconia, alumina, or a combination of two or more of these mentioned. 28. Method according to claim 13, CHARACTERIZED by the fact that at least one metal oxide is chosen from ZrO ₂ , CeO ₂ , Y ₂ O ₃ , TiO ₂ , Fe ₂ O ₃ , NiO, AI ₂ O ₃ , Cr ₂ O ₃ , Mo ₂ O ₃ , HfO ₂ , La ₂ O ₃ , Pr ₂ O ₃ , Nd ₂ O ₃ , Sm ₂ O ₃ , Eu ₂ O ₃ , Gd ₂ O ₃ , Tb ₂ O ₃ , Dy ₂ O ₃ , Ho ₂ O ₃ , Er ₂ O ₃ , Tm ₂ O ₃ , Yb ₂ O ₃ , Lu ₂ O ₃ , and combinations of two or more of these mentioned. 29. Method for the formation of at least one metal oxide on an internal surface of a system for processing or transporting an industrial fluid or its component, CHARACTERIZED by the fact that it comprises: place at least one first “pig” as close to the internal surface of the processing or transport system as an industrial fluid or a component thereof; apply at least one first metallic compound on the internal surface with at least one first “pig”; heating the internal environment of the surface to a temperature ranging from about 400 ° C to about 427 ° C; place at least one second “pig” as close to the inner surface of the processing or transportation system as an industrial fluid or component; applying at least a second metallic compound on the inner surface with at least a second "pig", where the at least one first metallic compound and at least one second metallic compound are the same or different; and, heat the environment of the inner surface to a temperature ranging from about 5 438 ° C to about 604 ° C, thereby forming at least one metal oxide on the inner surface. 30. Method, according to claim 29, CHARACTERIZED by the fact that one or both heating steps are carried out in the presence of nitrogen and in the substantial absence of oxygen.