KR100472337B1 - Process for producing metallic protective layer using hydrocarbon stream - Google Patents

Abstract

The present invention relates to a metallic protective layer which is subjected to plating, cladding, paint or other coating of metal-containing metal on at least one side of the reaction system and then contacted with a gas stream containing a hydrocarbon such as impurity hydrogen to produce a continuous and tacky metallic protective layer. It relates to a manufacturing method. The gas stream preferably comprises hydrogen and may be recycled hydrogen. Preferred aspects of the invention include the formation of a protective layer as part of the reaction system already protected in the finishing step is replaced or rewelded and the exchange part is onstream.

Description

A method of making a metallic protective layer using a hydrocarbon stream.

The present invention relates to a novel process for producing a metallic protective layer on a substrate such as steel using a hydrocarbon containing stream such as an impurity hydrogen stream. In particular it applies to finishing parts of the reaction system that have already been replaced or modified. The novel preparations of the invention can be applied to some or all of the reaction systems used to convert hydrocarbons.

It is known to form metallic protective layers on carburization-sensitive surfaces such as steel surfaces used in other hydrocarbon conversion environments such as cryogenic sulfur reforming (see WO92 / 15653) and hydrodealkylation (see WO92 / 15653). It is. These applications indicate that a cure step with pure hydrogen is required to form the metallic protective layer.

Unfortunately, without hydrogen facilities nearby, it is difficult to get pure hydrogen free hydrocarbons and it will be expensive. Moreover, using pure hydrogen is generally limited to one. This is because hydrogen recycling is generally not possible, since most recycled gas compressors, such as hydrocarbon-free hydrogen, cannot handle low molecular weight gases. Pure hydrogen can be diluted with an inert gas (eg nitrogen) to solve this recycling problem. Again compression and recycling will be attempted. However, nitrogen is also difficult to purchase and expensive. In summary, the need for one-time limited hydrogen or the addition of inert gas increases the cost of the treatment step.

The prior art with regard to the preparation and curing of metallic protective layers teaches the use of hydrocarbon-free hydrogen streams. For example, in Jose et al. WO92 / 15653, "The metallic coating and in particular the paint is preferably treated with hydrogen under reducing conditions. The curing is preferably carried out in the absence of hydrocarbons (p25, lines 23-5). . "

Almost the same can be found in Jose et al. WO 94/15898 (pages 23, lines 5-7). These two applications are incorporated herein by reference and will be cited with reference to particularly useful coating materials and curing conditions.

As a known treatment process, the initiation process after applying or painting a metal containing coating to a steel substrate comprises the following steps:

1. Heat the reaction system to a curing temperature (typically 600-1800 ° F.) in a hydrogen environment;

2. kept at cure temperature under hydrogen for 3 days;

3. cool the reaction system; again

4. Start the standard procedure of start-up.

The novel process of the present invention eliminates three of these steps; It is used in the "normal", "standard" or somewhat modified initiation stage, ie in the presence of the feedstock, to form the metallic protective layer in its original position. This does not require time-consuming and separation treatment steps using pure or hydrocarbon-free hydrogen. Thus, the new process reduces onset time and increases on-stream time by three days.

The novel process of the present invention is particularly useful for touch-up situations. For example, it can be used to form a metallic protective layer over a portion of a furnace tube that requires replacement. Remove the tube, remove it and replace it with a new steel piece. This part is coated or painted with a metal-containing coating and welded back in place. The protective layer is formed in situ as the tube is heated and heated in the presence of a hydrocarbon feedstock.

Summary of the Invention

In one embodiment, a method of forming a continuous and tacky metallic protective layer on a steel substrate using a gas stream containing a significant amount of hydrocarbons. The present invention is particularly useful in modified positions where part of the precoated and protected reaction system is replaced or cut open and then resealed.

In another embodiment, the present invention is directed to a method of making a metallic protective layer by applying a metal containing plating, cladding, paint or other coating agent to one or more reaction system surfaces. The coated surface is again contacted with a gas stream comprising a hydrocarbon that creates a metallic protective layer. The hydrocarbon contacting step occurs before the tacky metallic protective layer is produced or before it is fully cured.

As another example, the invention applies to a portion of the reaction system used to convert hydrocarbons. Here, the feedstock hydrocarbons are converted to the desired products in the reaction system with improved resistance to carburization and metal dusting, where the metal carburizing-resistant protective layer is formed on at least a portion of the reaction system and plated to produce the metallic protective layer. An improvement is achieved by producing the protective layer by contacting a gas stream containing hydrocarbons, cladding, paint or other coated metals and hydrocarbons.

It is also preferred that the hydrocarbon-containing stream contains hydrogen, ie the contacting takes place in a reducing environment. One preferred hydrocarbon-containing stream is a feedstock for a hydrocarbon conversion process comprising feedstock hydrogen. Another is impurity hydrogen.

The present invention, unlike the prior art, does not interfere with the formation of a continuous protective layer during the curing step in the presence of hydrocarbons. Prior to the present invention, the presence of hydrocarbons and the interaction of these hydrocarbons with the coated metal or steel surface were thought to hinder or adversely affect the formation of continuous and tacky metallic protective layers.

The present invention has great advantages over other methods. The use of hydrocarbon-free hydrogen eliminates the need for a separate curing step, simplifying and reducing the initiation process time for the reaction system or a portion of the reaction system. It also provides a readily available feed stream or a low cost impurity hydrogen stream for preparing protective coatings. In addition, the impurity hydrogen stream can be used once without significant cost. Thus, the use of hydrocarbon-containing feedstock for the curing step reduces the cost of producing the protective layer. Moreover, the new preparation clearly simplifies the procedure for forming the protective layer, in particular the initiation step.

As a general scope, the present invention is directed to a process characterized by the creation of a metallic protective layer on a base substrate such as steel in the presence of a significant amount of hydrocarbons. In a preferred embodiment, a protective layer is formed by contacting a stream containing hydrocarbons with a metal containing paint, preferably a reducing paint (eg tin paint) at an effective temperature and flow rate for converting the paint into a metallic protective layer. Let's do it.

The term " characterizing " as used throughout this application will include the terms " essentially configuring " and " constituting " in various preferred embodiments of the present invention.

As used herein, a "reactor system" will include a hydrocarbon conversion unit comprising one or more hydrocarbon conversion reactors, pipes connected thereto, heat exchangers, furnace tubes, and the like. Some of the preferred hydrocarbon conversion methods useful in the present invention employ sulfur sensitive catalysts. There may be a sulfur conversion reactor for converting the organic sulfur compound into H ₂ S and a sulfur absorption reactor for absorbing H ₂ S. When they are present they are included in part of the reaction system.

As used herein, the term "metal-containing coating" or "coating" includes cladding, plating, paints and other coatings including base metals, metal oxides, organometallic compounds, metal alloys, mixtures of these components, and the like. something to do. Metals or metal compounds are preferably important coating components. Flowable paints are sprayed or brushed as the preferred coating form.

Plating, cladding, paints and other coatings

Not all metal containing, plating, cladding, paints and other coatings are useful in the present invention. Preferred metals interact and preferably react with the base material of the reaction system at temperatures below and below the intended hydrocarbon inversion conditions for producing the tacky metallic protective layer. Preferred metals depend on the temperature, reactants, etc., which are of interest to the hydrocarbon conversion method. These metals include those selected from tin, antimony, germanium, arsenic, bismuth, aluminum, gallium, indium, copper, lead and mixtures thereof, intermetallic compounds and alloys thereof. Preferred metal containing coatings include those selected from tin, antimony, germanium, arsenic, bismuth, aluminum, and mixtures thereof, intermetallic compounds and alloys thereof. Particularly preferred coatings include tin-, antimony- and germanium-containing coatings. All these coatings form a continuous and tacky protective layer. Tin coatings are particularly preferred and they are readily applied to steel, inexpensive and have low environmental risks.

Less useful metal-containing coatings are certain metal oxides such as molybdenum oxide, tungsten oxide and chromium oxide. In part this is because under most hydrocarbon reaction conditions it is difficult to form a tacky metallic protective layer from these oxides using a stream comprising hydrogen and hydrocarbons.

It is desirable to coat the coating sufficiently thick so that the coating completely covers the base metal and the resulting protective layer is not damaged by years of operation. The thickness depends on the intended conditions of use and the metal. For example, the tin paint can be painted with a (wet) thickness of 1 to 6 mm, preferably 2 to 4 mm. In general, the thickness after the treatment is preferably about 0.1 to 50 mm, more preferably about 0.5 to 10 mm.

Metal-containing coatings may utilize various methods of the prior art, for example electroplating, chemical vapor cracking and sputtering. Preferred coating application methods include paint and plating. In practice, it is desirable that the coating be applied to paint like forms (hereinafter referred to as "paint"), and these paints can be sprayed, brushed, or pigged on the reaction system surface.

Preferred protective layers can be prepared from metal containing paints. Preferably, the paint is a degradable, reactive paint and a metal containing paint that produces a reactive metal that interacts with the steel. Tin is a preferred metal and is exemplified herein; The description of tin herein is generally applicable to other reducing metals such as germanium. Preferred paints comprise metal components selected from the group comprising finely ground metals such as organometallic compounds and hydrogen decomposable metal compounds which are metal oxides, preferably reducing metal oxides.

Some preferred coatings are described in WO 92/15653 to Jose et al. This application also describes preferred paint forms. Particularly preferred tin paints include at least the following four components or components such as these functions; (i) hydrogen decomposable tin compound, (ii) solvent system, (iii) finely ground tin metal and (iv) tin oxide. Organometallic compounds such as tin octanoate or neodecanoate are particularly useful, such as hydrogen decomposable tin compounds. The tin oxide of component (iv) is a porous tin containing compound that can be sponge-up with an organometallic tin compound and can be reduced to metallic tin. The paint preferably comprises finely ground solids to minimize precipitation. The finely ground tin metal of component (iii) is also metallic tin that can react with the surface which can be coated at the lowest possible temperature. The fine particle size of tin is preferably as small as 1 to 5 microns. When heated in a stream containing hydrogen and hydrocarbons, tin forms metallic stannides (eg tin iron and tin nickel / iron stanide).

As an example, tin paints containing tin oxide (II), tin metal powder, isopropyl alcohol, and 20% Tin Ten-Cem (manufactured by Ohio, Cleveland, Monik Chemical Incorporated) can be used. 20% Tin Ten-Cem comprises 20% tin in the form of stannous neodecanoate in stannous ocatanate or neodecanoic acid in octanoic acid. If tin paint is applied at a suitable thickness, typical reactor starting conditions will allow tin to move to cover a small area that is not painted (such as welding). This will completely coat the base metal. Preferred tin paints form a strong tacky protective layer early in the initiation reaction.

Iron-containing reactive paints are also useful in the present invention. Preferred iron containing reactive paints will contain various tin compounds in which iron is added in an amount of up to one third of the Fe / Sn weight. For example, it can be Fe ₂ O ₃ by the addition of iron. Iron added to tin has significant advantages; In particular: (i) the reaction of the paint forming iron stannide is facilitated and acts as a flux; (ii) dilution of nickel concentration in the stanid layer to provide better protection against caulking; (iii) Provide a paint that provides anti-caulking protection of the iron stanid even if the underlying surface does not react well.

Hydrocarbon-containing streams

The hydrocarbon containing stream is used to form a protective layer on the metal surface of the reaction system. One useful stream is impurity hydrogen (eg methane containing hydrogen). Impurity hydrogen streams are often used in purification and chemical plants. They generally contain at least 1% by volume, often at least 10% hydrocarbons. Impurity hydrogen is a low cost stream used as fuel. The inventors have discovered that these impurity streams can be used to produce sticky and continuous metallic protective layers. Examples of these two streams are shown in the table below:

Stream 1 is a common fluid catalytic cracker (FCC) fuel gas composition. Stream 2 is a common reformed fuel gas. Although not required, as one preferred embodiment, the non-hydrocarbon impurities in the gas stream should be minimized. For example, H ₂ S, water, and organic sulfur-, oxygen- and nitrogen-containing compounds are removed.

Other streams that can be used to form the protective layer are, for example, hydrocarbon feedstocks that include recycled hydrogen required in processes requiring a protective layer. The hydrocarbons in the stream are preferably selected from hydrocarbons comprising naphthenes, paraffins, aromatics, alkylaromatic olefins and methane containing light gases. Paraffin streams are preferred. The hydrocarbonaceous stream may be mixed or combined with other gases such as carbon monoxide and nitrogen. It is important that the treatment stream is selected so that the protective layer is not attacked or damaged. The preferred stream thus varies depending on the particular form of metal containing coating used. For example, halogen containing streams contaminate several types of metal coatings. In particular, one preferred stream comprises a dry hydrocarbon feedstock or a product combined with hydrogen.

In particular, one preferred stream is a mixture of hydrocarbons and hydrogen containing 1 to 90% by volume of hydrocarbons in hydrogen, preferably containing at least 10% by volume, more preferably about 15 to 40% by volume. For example, fixed bed catalyst reformed feedstock streams are useful. Generally, the molar ratio of hydrogen to hydrocarbon is about 3: 1 to 10: 1. Although not required, it is desirable to use recycled hydrogen streams for significant cost savings. When hydrocarbons in the hydrogen are present, the recycle gas compressor will operate as a design element.

While not clearly understood at present, it appears that coatings with hydrocarbon-containing streams and / or sulfur compounds form a protective layer about 50% thicker than that produced in pure hydrogen. These thicker layers are expected to increase protection to the base substrate.

Cure Process Conditions

The curing step of the present invention contacts the coated steel at an elevated temperature with a gas hydrocarbon containing stream such as raw material, product, or impurity hydrogen. Curing conditions depend on the coating metal and are chosen such that the steel substrate is coated with a continuous, unbreakable protective layer. Contacting the gas hydrocarbon containing stream takes place while the protective layer is formed. No curing step with pure hydrogen is necessary. The resulting protective layer can withstand repeated temperature cycling and does not break down in the reaction environment. In addition, preferred protective layers are useful in the oxidizing environment associated with coke combustion. In a preferred embodiment, the curing step produces a metallic protective layer bonded with the steel through an intermediate bonding layer, such as a carbide-rich bonding layer.

Curing conditions depend on the specific metal coating as well as the hydrocarbon conversion method applied in the present invention. For example, the gas flow rate and contact time depend on the treatment temperature, the coating metal and the components of the coating composition. Curing conditions are selected to produce an adhesive protective layer. In general, the process of the present invention contacts the hydrocarbon-containing gas with a metal-containing coating, plating, cladding, paint or other coating applied to a portion of the reaction system for a temperature and time sufficient to produce a metallic protective layer. These conditions can be easily determined. For example, the coated coupon is heated in the presence of a hydrocarbon containing gas in a simple test apparatus; The formation of the protective layer can be determined using petrographic analysis.

It is desirable to form a protective layer that is firmly bonded to steel under curing conditions. This can be done by curing the applied coating at increased temperature. Metals or metal compounds contained in paints, platings, claddings or other coatings are preferably cured under conditions effective to produce mobile metals and / or compounds. Therefore, germanium and antimony paints are preferably cured at 1000 to 1400 ° F. Curing is preferably carried out over several hours, and the time increases with increasing temperature. Preferred metallic protective layers derived from these paints are preferably produced under reducing conditions. The reduction / cure is done at high temperature in the presence of a hydrogen containing hydrocarbon stream. The presence of hydrogen is particularly preferred when the paint comprises a reducing oxide and / or an oxygen containing organometallic compound.

As an example of a suitable paint cure for tin paint, a system comprising a painted portion may be pressurized with nitrogen flow and the addition may be carried out with a hydrocarbon containing stream of hydrogen to naphtha 1: 1. The reactor inlet temperature can be elevated to 800 ° F. at a rate of 50-100 ° F./hour. The temperature can then be raised from 50 ° F./hour speed to 950-975 ° F. and maintained in this range for about 48 hours.

In one embodiment of the invention, the metallic protective layer can be prepared during plant start-up. However, it is important that the treatment does not contaminate the catalyst or clog the pores when the catalyst is present. The usefulness of this procedure therefore depends on the presence or location of catalyst in the reaction system and the sensitivity of the catalyst to the coating metal. The method of the present invention is applied to furnace tubes, heat exchangers, pipes and the like which are not adjacent to the catalyst bed or immediately preceding the catalyst bed.

If catalytic poisons are involved, stray metals should be prepared so that they do not come into contact with the catalyst. For example, curing may be completed prior to catalyst loading, or catalyst may be removed in the curing step. Optionally a catalyst may be present and an absorber or collector for the derailed metal, such as a high surface area alumina or silica protective layer, may be used upstream of the catalyst bed. In one embodiment, a new hydrocarbon conversion catalyst or catalyst removed from the reactor after the curing step is introduced into the reaction system.

Base component

There are a variety of base materials that can be applied to the present invention. In particular, a wide range of steels can be used in the reaction system. In general, steel is selected that is suitable for the minimum strength and flowability of the requirements required for the intended hydrocarbon conversion. These requirements depend on reaction conditions such as operating temperature and pressure.

Useful steels are carbon steels; Low alloy steels such as 1.25, 2.5, 5, 7 and 9 chrome steels; Stainless steel, including 340 stainless steel such as 346 and 316SS; Heat treated steels including HK-40 and HP-50 as well as treated steels such as aluminized steel or chromized steel. Preferably the steel contains iron and chromium in an oxidation state of zero.

The reaction of the coated reaction system metallurgy can occur because the reaction depends on the components of the metal containing coating. Preferably, the reaction forms a carbide-rich binding intermediate, or a glue layer that is firmly anchored to steel and is not easily peeled off. For example, metallic tin, germanium and antimony (whether directly clad or in situ) readily react with steel at high temperatures to form a bonding layer, as described in WO 94/15898 or WO 94/15896 of Jose et al. do.

Desirable applications

The present invention for producing a metallic protective layer can be used to protect even one or more large parts of the reaction system or only a small part thereof. As a preferred embodiment, the present invention has been used to modify a relatively small portion of a reaction system that already has a metallic protective layer applied to the reaction system. For example, part of the reaction system must be replaced due to a change or failure in the process configuration. For example, part of the furnace tube or part of the reactor screen may need to be replaced. Here, the furnace tube or a part of the tube may be separated or brought off-line. The tube or some replacement thereof is again coated with a metal containing coating, plating, cladding or paint. The coated tube can be left on-stream in the presence of the feedstock again without a separation treatment step. It is coated in place to produce a protective layer.

The invention also provides a new, a protective layer on the replacement part, or a newly manufactured or re-welded moving pipe for reactor media (eg, streams, distributors, associated pipes, central pipes and screens thereof) requiring replacement. , To form a protective layer on the flange and the nozzle.

Application to hydrocarbon telephony

The reaction system having a metallic protective layer prepared by the novel process of the present invention is effective for reducing coking and / or carburization of various hydrocarbon conversion reactions. Therefore, the novel method of the present invention for producing a protective layer can be applied to all or some reaction systems of hydrocarbon conversion.

Preferred hydrocarbon conversion reactions include the following reactions: dehydrocyclization from C ₆ and / or C ₈ paraffins to aromatics; Catalytic reforming; Non-oxidative and oxidative dehydrogenation of hydrocarbons to olefins and dienes; Dehydrogenation of ethylbenzene to styrene and / or dehydrogenation of isobutane to isobutylene; Conversion of light chain hydrocarbons to aromatics; Transalkylation from toluene to benzene and xylene; Hydrodealkylation from alkylaromatics to aromatics; Alkylation of alkylaromatics in aromatics; Production of fuels and chemicals from syngas (H ₂ and CO); Steam reforming from hydrocarbons to H ₂ and CO; Preparation of phenylamine in aniline; Methanol alkylation of toluene to xylene; And dehydrogenation of isopropyl alcohol to acetone. Preferred hydrocarbon conversion reactions include conversion of light chain hydrocarbons to aromatics such as dehydrocyclization, catalytic reforming, dehydrogenation, isomerization, hydrodealkylation and Cyclar-type reactions. In a preferred embodiment, when dehydrogenating from paraffins to olefins or paraffin feedstock containing C ₆ and / or C ₈ hydrocarbons into aromatics (eg in the reaction to produce benzene, toluene and / or xylene) In order to dehydrogenate a catalyst, preferably a platinum catalyst, may be used.

The present invention is particularly applicable to hydrocarbon conversion reactions in which noble metal catalysts containing Pt, Pd, Rh, Ir, Ru, Os, in particular catalysts containing platinum, are required. These metals are generally provided on supports such as carbon, on refractory oxide supports such as silica, alumina, chlorided alumina or on molecular sieves or zeolites. Preferred catalytic reactions include noble metal Group VIII catalysts supported on zeolites such as platinum on alumina, Pt / Sn on alumina and Pt / Re Pt on alumina chloride, Pt / Sn and L-type zeolites, ZSM-5, SSZ-25, Pt / Re on zeolite containing silicalite and beta of SAPO is used.

As a preferred embodiment, the present invention uses a mesoporous or macropore sized zeolite catalyst containing an alkali or alkaline earth metal and filled with one or more Group VIII metals. Particularly preferred catalysts for use in the present invention are L-zeolite catalysts containing platinum, preferably Group VIII metals on macroporous zeolites such as platinum on non-acidic L zeolites. Useful platinum catalysts on L zeolites are described in US Pat. No. 4,634,518 to Booth and Hue, US Pat. No. 5,196,631 to Murakawa et al., US Pat. No. 4,593,133 to Wartel and US Pat. have.

The present invention can be used in particular for hydrocarbon conversion reactions operated under reduced or low sulfur conditions or in combination with sulfur removal reactions using various sensitive catalysts. These reactions are known in the prior art. These reactions generally require purification of the feedstock, such as hydrotreating and / or sulfur adsorption. These include catalyst reforming and / or dehydrocyclization as described in US Pat. No. 4,456,527 to Booth et al. And US Pat. reaction; And catalytic hydrogenation / dehydrogenation reactions.

In a particularly preferred embodiment, the hydrocarbon conversion reaction is carried out under "low sulfur" conditions. In these low sulfur systems, the feedstock will preferably contain up to 50 ppm, more preferably up to 200 ppm and most preferably up to 10 ppm sulfur.

When using sulfur contaminated catalysts, the hydrocarbon sulfur level is preferably such that the catalyst performance is not significantly reduced. This sulfur level depends on the particular catalyst. Generally, sulfur levels are low levels of 5 ppm or less, preferably 1 ppm or less, more preferably 500 ppm or less. For catalysts that are very susceptible to sulfur, sulfur levels should be at very low levels of 100 ppb, preferably 50 ppb, and more preferably 10 ppb or less. These substantially sulfur-free gases are also preferably free of oxygen-containing and nitrogen-containing contaminants such as ammonia or water.

Sulfur compound containing and other contaminant containing gases can be treated to remove these contaminants. In addition to hydrotreating and mild reforming and adsorption reactions, several reactions used for this purpose through the prior art will be used by those skilled in the art.

In order to facilitate a more complete understanding of the present invention, the following examples of specific fields of the invention are illustrated. However, the present invention is not intended to be limited to any particular description of the examples.

Example 1

This experiment was conducted using 1/4 inch O.D. The reactor was used in a pilot plant. The reactor was covered with tin containing paint. As described in WO 92/115653, the paint comprises two parts of powdered tin oxide, two parts of finely powdered tin (1-5 microns), neodecanoic acid (20% tin Tem mixed with isopropanol) It consists of a mixture of 1 part tinstande neodecanoate in Cem). The inner surface of the tube was covered by filling the tube with paint and draining the paint.

After drying, the hydrocarbon-containing stream comprising 100 ppmv H ₂ S, 50% by volume of n-hexane and the remaining hydrogen is provided at a flow rate of 50 standard cm ³ per minute at atmospheric pressure and room temperature. The reactor was again heated to about 1100 ° F. for 30 hours and held for another 60 hours with flowing gas at this temperature. The reaction gas was used for single use.

After this process was completed, the reactor was opened and the resulting layer was visually inspected. There was little coke on this steel surface. The steel cross section is coated with epoxy and polished. They were again examined using rock classification and electron scanning microscopy. Micrographs show that tin paint reduces metallic tin under these conditions. A continuous and tacky metallic (iron / nickel stannide) protective layer with a thickness of about 30 microns was observed on the steel surface.

Example 2

The procedure of Example 1 was repeated using a gas containing 35% by volume n-hexane and the remaining hydrogen. Sulfur was not added. As in Example 1, a continuous and tacky metal protective layer was formed on the steel surface.

Although the invention has been described as such preferred embodiments, those skilled in the art will recognize that there are variables and variations that can be used. Those skilled in the art can easily add variables and modifications to these aspects and will fall within the scope defined in the following claims.

Claims (19)

A method of providing a metallic protective layer in a replacement part of a reaction system, Replacing an existing portion of the reaction system with a replacement portion; Applying metal-containing plating, cladding, paint or other coating to the replacement portion; And In order to cure the metal-containing plating, cladding, paint or other coatings, the reaction system is operated using a gas stream comprising hydrogen and at least 10 volume percent hydrocarbons, thereby continuing to a preexisting adjacent metallic protective layer. Providing a metallic protective layer on said replacement portion. The method of claim 1, The metal-containing plating, cladding, paint or other coating agent consists of tin, antimony, germanium, arsenic, bismuth, aluminum, gallium, indium, copper, lead, and mixtures thereof, intermetallic compounds and alloys thereof A method for producing a metallic protective layer, characterized in that it comprises one metal selected from the group. The method of claim 1, The metal-containing plating, cladding, paint or other coating agent comprises a metal selected from the group consisting of tin, antimony and germanium. The method of claim 1, And wherein the metal-containing plating, cladding, paint or other coating agent comprises tin paint. The method of claim 1, Wherein said gas stream is impure hydrogen or fuel gas. The method of claim 1, The gas stream is a hydrocarbon feedstock to the reaction system. The method of claim 6, Wherein said hydrocarbon feedstock is a paraffinic stream. The method of claim 6, Wherein the hydrocarbon feedstock further comprises carbon monoxide (CO). The method of claim 6, Wherein said hydrocarbon feedstock further comprises nitrogen. The method of claim 1, Wherein said gas stream comprises about 15 to 40 volume percent hydrocarbons. The method of claim 1, Wherein said gas stream comprises methane. The method of claim 1, The metallic protective layer is a method of manufacturing a metallic protective layer, characterized in that it comprises iron stannide (iron stannide). The method of claim 1, And said operating step further comprises operating said reaction system under typical starting conditions for curing said metal-containing plating, cladding, paint or other coating agent. The method of claim 1, And said operating step further comprises operating said reaction system under typical operating conditions for curing said metal-containing plating, cladding, paint or other coating agent. The method of claim 1, And the replacement portion comprises a portion of a furnace. A method of providing a metallic protective layer on a replacement portion of a reaction system, Adding a catalyst to the reaction system; Replacing the existing portion of the reaction system with a replacement portion; Applying metal-containing plating, cladding, paint or other coating agent to the replacement portion; And In order to cure the metal-containing plating, cladding, paint or other coatings, the reaction system is operated using a gas stream comprising hydrogen and at least 10 volume percent hydrocarbons, thereby continuing to a preexisting adjacent metallic protective layer. Providing a metallic protective layer on said replacement portion. The method of claim 16, The catalyst is a method of producing a metallic protective layer, characterized in that the sulfur-sensitive catalyst. The method of claim 16, Wherein said gas stream comprises less than or equal to about 5 ppm sulfur. The method of claim 16, Wherein said gas stream comprises up to about 10 ppb of sulfur.