Catalyst for methane reforming and its manufacturing method

Abstract

A methane reforming catalyst according to one embodiment of the present application includes a porous metal support; a first coating layer provided on the porous metal support and containing a perovskite-based compound represented by Chemical Formula 1 above; and a second coating layer provided on the first coating layer and containing a perovskite-based compound represented by Chemical Formula 2 above.

Description

[Technical field]

[0001] This application claims the benefit of the filing date of Korean Patent Application No. 10-2021-0159456, filed with the Korean Intellectual Property Office on November 18, 2021, the entire contents of which are incorporated herein by reference.

[0002] The present application relates to a catalyst for methane reforming and a method for producing the same. [Background technology]

[0003] As part of efforts to reduce greenhouse gas emissions due to global warming, much research is being conducted on carbon dioxide conversion technologies. Carbon dioxide reforming, one of the carbon dioxide conversion technologies, is a technology in which methane and carbon dioxide are reacted to produce synthesis gas consisting of hydrogen and carbon monoxide.

[0004] Syngas is a valuable substance for development as a raw material for various downstream processes. Natural gas reforming reactions, which can industrially produce syngas (H2 / CO), can be roughly classified into steam reforming, CO2 reforming, catalytic partial oxidation, autothermal reforming, and tri-reforming, as shown in the following reaction formulas 1 to 5. [Reaction Scheme 1] CH4+H2O → 3H2+CO △H=226kJ / mol [Reaction Scheme 2] CH4+CO2→ 2H2+2CO △H=261kJ / mol [Reaction Scheme 3] CH4+0.5O2→ 2H2+CO △H=-44kJ / mol [Reaction Scheme 4] Autothermal reforming: Reaction 1 + Reaction 3 [Reaction Scheme 5] Tri-reforming: Reaction 1 + Reaction 2 + Reaction 3

[0005] Meanwhile, various catalysts can be used in the reforming process for the purpose of reforming activity. Among them, when a precious metal catalyst is used in the reforming process, the efficiency of converting natural gas into hydrogen is high, but the precious metal catalyst is expensive, which reduces the economic efficiency.

[0006] For this reason, nickel catalysts, which have high hydrogen conversion efficiency and are relatively inexpensive, are mainly used in the reforming process, but in such cases, there is a problem that the nickel catalyst is deactivated by carbon that is inevitably generated on the surface of the nickel catalyst.

[0007] Therefore, there is a need in the art to develop a catalyst that is resistant to carbon deposition and can be effectively applied in the methane reforming process. Summary of the Invention [Problem to be solved by the invention]

[0008] The present application seeks to provide a catalyst for methane reforming and a method for producing the same. [Means for solving the problem]

[0009] One embodiment of the present application comprises: porous metal support; a first coating layer provided on the porous metal support and including a perovskite-based compound represented by the following chemical formula 1; and A second coating layer provided on the first coating layer and containing a perovskite-based compound represented by the following chemical formula 2: The present invention provides a catalyst for methane reforming, comprising: [Chemical formula 1] SrTiO3 [Chemical formula 2] Sr 1-x A x Ti α B y O3-δ In the above Chemical Formula 2, A is selected from Y, Sc, La and the Lanthanide series elements; B is Ni, Co, Fe, Mn, Cr, Mo, Ru or Rh; x is a real number between 0 and 1, y is a real number greater than or equal to 0 and less than 0.3, δ is a real number between 0 and 1, α is a real number greater than 0.7 and less than or equal to 1, Satisfies (x+y)>0.

[0010] In addition, another embodiment of the present application is Preparing a first solution containing a precursor of the perovskite compound represented by the above Chemical Formula 1; and a second solution containing a precursor of the perovskite compound represented by the above Chemical Formula 2; Coating the porous metal support with the first solution and then carrying out a first heat treatment process to prepare a catalyst precursor having a first coating layer; and coating the catalyst precursor having the first coating layer with the second solution, and then performing a second heat treatment process to prepare a catalyst having a second coating layer; The present invention provides a method for producing a catalyst for methane reforming, comprising the steps of: Effect of the Invention

[0011] In the methane reforming catalyst according to one embodiment of the present application, a first coating layer containing a perovskite-based compound represented by Chemical Formula 1 without a catalytic component is formed, which not only improves adhesion between the porous metal support and the second coating layer containing a perovskite-based compound represented by Chemical Formula 2, but also prevents side reactions of the porous metal support.

[0012] In addition, the methane reforming catalyst according to one embodiment of the present application has a perovskite-based compound supported on a porous metal support having high thermal conductivity, and therefore has the characteristic that the reaction heat can be easily controlled compared to conventional pellet-shaped or powder-shaped catalysts.

[0013] In addition, the methane reforming catalyst according to one embodiment of the present application can increase the active surface area of ​​the catalyst, and therefore can exhibit high activity even at a high space velocity during the methane reforming reaction. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram showing an electron microscope photograph of the surface of a methane reforming catalyst according to Example 1 of the present application. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] This specification will be explained in more detail below.

[0016] In this specification, when a member is said to be located "on" another member, this includes not only the case where the member is in contact with the other member, but also the case where there is another member between the two members.

[0017] In this specification, when a part is said to "comprise" a certain component, this means that it can further include other components, not excluding other components, unless specifically stated to the contrary.

[0018] Currently, catalysts widely used in the field of reformers are generally powder catalysts and pellet support catalysts. The powder catalysts have excellent dispersion and performance, but it is difficult to use them directly in industry. For example, when the powder catalyst is used to drive the reformer, the catalyst comes out together with the material produced after the reaction, and at this time, the powder catalyst gradually accumulates in the flow tube at the outlet, eventually clogging the entire tube. Therefore, there is a disadvantage that the powder catalyst cannot be used in commercial reformers used in industry.

[0019] In addition, the pellet-type support catalyst is currently widely used in industrial reformers. Due to the limitations of the mass transfer rate, it is inferior to powder-type catalysts in terms of catalytic performance alone, but it has the advantage of being able to be used for a long time because of the use of a support. However, in the case of γ-Al2O3 pellets, which are widely used as the pellet-type support catalyst, it has a disadvantage that it is easily broken due to its weak structural strength, which causes a pressure difference in the reactor. In addition, due to the characteristics of the pellet-type support catalyst, it is large in volume, so when it is used in a high-capacity reformer, the volume becomes quite large. In addition, all reforming reactions are sensitive to the reaction temperature, but in the case of existing pellet-type catalysts, there is a disadvantage that the thermal conductivity is greatly reduced and heat is not distributed evenly throughout the reactor. In addition, in the case of reforming reactions, the reaction is very fast, and in the case of pellet-type support and extrusion-molded catalysts, the effectiveness factor of the catalyst is 0.3 or less, which reduces the effectiveness of the catalyst.

[0020] Therefore, this application aims to improve not only the phenomenon of flow tube clogging, which is a drawback of powder, but also the common drawback of powder and pellet-type, the heat and mass transfer rate, by coating a catalyst on a porous metal support having a high heat and mass transfer rate. In addition, this application aims to provide a catalyst for methane reforming that can support a large amount of catalyst at one time and suppress side reactions caused by the binder.

[0021] A methane reforming catalyst according to one embodiment of the present application includes a porous metal support; a first coating layer provided on the porous metal support and containing a perovskite-based compound represented by Chemical Formula 1 above; and a second coating layer provided on the first coating layer and containing a perovskite-based compound represented by Chemical Formula 2 above.

[0022] In one embodiment of the present application, the perovskite-based compound represented by the above Chemical Formula 1 is a compound without a catalytic component, and the perovskite-based compound represented by the above Chemical Formula 2 is a compound containing a catalytic component (A and / or B in Chemical Formula 2), and they are different from each other.

[0023] In one embodiment of the present application, the above Chemical Formula 2 can be represented by the following Chemical Formula 3 or 4. [Chemical formula 3] SrTi α B y O 3-δ [Chemical formula 4] Sr 1-x Y x Ti α B y O 3-δ In the above formulas 3 and 4, B is Ni or Ru; x is a real number greater than 0 and less than 1, y is a real number greater than 0 and less than 0.3, δ is a real number greater than 0 and less than 1, α is a real number greater than 0.7 and less than or equal to 1.

[0024] In one embodiment of the present application, the porous metal support may be made of a material capable of maintaining thermal stability at high temperatures of 800° C. or higher.

[0025] In one embodiment of the present application, the porous metal support may be a metal foam comprising NiFeCrAl, NiCrAl, SiC or α-Al2O3.

[0026] The porous metal support may have various shapes, and has a small heat capacity and excellent heat transfer ability, and can be formed into a desired shape for use. The shape and size of the porous metal support are not particularly limited, and the porosity of the porous metal support may be 10% to 99%, 50% to 96%, or 85% to 96%. The average pore size of the porous metal support may be 400 μm to 2,000 μm, or 450 μm to 1,500 μm. If the average pore size of the porous metal support is less than 400 μm, it is difficult to coat the precursor solution, and if it exceeds 2,000 μm, it is not preferable because the surface area that can be coated with the catalyst is reduced, which is disadvantageous in the process. The porous metal support may be appropriately prepared by a person skilled in the art using a method known in the art, taking into consideration the material, pore size, porosity, etc. of the porous metal support. According to one embodiment of the present application, porous metal supports having various materials, pore sizes, etc. can be applied as described in the examples below.

[0027] In one embodiment of the present application, the content of the perovskite-based compound represented by Chemical Formula 1 may be 1 wt% to 20 wt%, or 1.5 wt% to 18 wt%, based on the total weight of the porous metal support. If the content of the perovskite-based compound represented by Chemical Formula 1 exceeds 20 wt%, the capacity for coating the perovskite-based compound represented by Chemical Formula 2 may be reduced, which is undesirable because the activity of the catalyst may be reduced compared to the volume of the porous metal support. In addition, if the content of the perovskite-based compound represented by Chemical Formula 1 is less than 1 wt%, the content is so small that it may be difficult to obtain the effect of the first coating layer.

[0028] In one embodiment of the present application, the weight ratio of the perovskite-based compound represented by the above chemical formula 1 to the perovskite-based compound represented by the above chemical formula 2 may be 1:1 to 1:20, or 1:1.1 to 1:15. If the weight ratio of the perovskite-based compound represented by the above chemical formula 1 to the perovskite-based compound represented by the above chemical formula 2 deviates from this range, the activity of the catalyst may be reduced compared to the volume of the porous metal support, which is not preferred.

[0029] In one embodiment of the present application, (α+y) in the above chemical formula 2 may be 1. Also, in one embodiment of the present application, (α+y) in the above chemical formula 2 may be a real number greater than 0.90 and less than 1. In the above chemical formula 2, B such as Ni replaces a portion of Ti, and in the theoretical stoichiometric ratio, (α+y) is 1, but when the Ti content is slightly less than the theoretical stoichiometric ratio during the preparation of the perovskite-based compound represented by the above chemical formula 2, the Ti in the chemical formula 2 can be more easily replaced by B such as Ni.

[0030] In one embodiment of the present application, the content of the perovskite-based compound represented by the formula 2 may be 3 wt% to 40 wt%, 6 wt% to 35 wt%, or 7 wt% to 30 wt% based on the total weight of the methane reforming catalyst. When the content of the perovskite-based compound represented by the formula 2 is less than 3 wt% based on the total weight of the methane reforming catalyst, the reactivity may be reduced due to the relatively small number of active sites on the catalyst surface, which is not preferable. In addition, when the content of the perovskite-based compound represented by the formula 2 exceeds 40 wt%, the catalyst contains a relatively large amount of catalyst components compared to the porous metal support, making it difficult to maintain the pore structure and difficult to bond the catalyst components to the porous metal support, which may reduce the practical benefit of the methane reforming reaction.

[0031] In one embodiment of the present application, the first coating layer can be provided on the entire surface of the porous metal support.

[0032] In one embodiment of the present application, at least a portion of the surface of the methane reforming catalyst includes a protruding shape, which may be in the form of, but is not limited to, a sphere, an ellipse, or a combination thereof.

[0033] In one embodiment of the present application, the first coating layer including the perovskite-based compound represented by Chemical Formula 1 may serve to fix the second coating layer including the perovskite-based compound represented by Chemical Formula 2 on the porous metal support. In addition, the second coating layer including the perovskite-based compound represented by Chemical Formula 2 may be present in a protruding shape on the first coating layer, thereby increasing the reaction surface area of ​​the catalyst and improving the performance of the methane reforming reaction.

[0034] According to one embodiment of the present application, the total content of catalyst supported on the porous metal support can be increased by simultaneously applying a first coating layer containing a perovskite-based compound represented by Chemical Formula 1 and a second coating layer containing a perovskite-based compound represented by Chemical Formula 2, compared to the case where catalyst particles are applied alone. According to one embodiment of the present application, the first coating layer containing a perovskite-based compound represented by Chemical Formula 1 can be applied to prevent the phenomenon in which metals (Ni, Cr, etc.), which are the main components of the porous metal support, are exposed to the surface in the form of metal oxides (NiO, Cr2O3, etc.) under long-term operating conditions at high temperatures (750°C or higher), and changes in the catalyst component ratio or catalyst phase of Chemical Formula 2 can be prevented, thereby improving the durability and performance of the catalyst.

[0035] In one embodiment of the present application, the methane reforming catalyst can be applied to a steam reforming process, a carbon dioxide reforming process, a catalytic partial oxidation process, an autothermal reforming process, a tri-reforming process, or a mixed reforming process, and the methane reforming process is not particularly limited.

[0036] A method for producing a methane reforming catalyst according to one embodiment of the present application includes the steps of: preparing a first solution containing a precursor of a perovskite-based compound represented by Chemical Formula 1; and preparing a second solution containing a precursor of a perovskite-based compound represented by Chemical Formula 2; coating a porous metal support with the first solution, and then performing a first heat treatment process to produce a catalyst precursor having a first coating layer; and coating the catalyst precursor having the first coating layer with the second solution, and then performing a second heat treatment process to produce a catalyst having a second coating layer.

[0037] In the method for producing a methane reforming catalyst according to one embodiment of the present application, the porous metal support, the perovskite-based compound represented by Chemical Formula 1, the perovskite-based compound represented by Chemical Formula 2, etc. are as described above.

[0038] In particular, the first solution containing the precursor of the perovskite-based compound represented by Chemical Formula 1 and the second solution containing the precursor of the perovskite-based compound represented by Chemical Formula 2 may be applied in the form of a sol or gel, respectively.

[0039] The precursor of the perovskite compound is a precursor of a metal constituting the perovskite compound, and the content of the precursor can be adjusted to adjust the metal molar ratio of the perovskite compound. The precursor of the metal is not particularly limited, and the ammonium salt, nitrate, carbonate, chloride, lactate, hydroxide, organic acid salt, oxide, or a mixture thereof of the metal element can be used.

[0040] A method for producing a methane reforming catalyst according to one embodiment of the present application includes the steps of preparing a first solution containing a precursor of a perovskite compound represented by the above chemical formula 1; and a second solution containing a precursor of a perovskite compound represented by the above chemical formula 2.

[0041] The first solution and the second solution may each independently further contain a solvent. The solvent may be any solvent known in the art and is not particularly limited.

[0042] A method for producing a methane reforming catalyst according to one embodiment of the present application includes the steps of: coating a porous metal support with the first solution, and then performing a first heat treatment process to produce a catalyst precursor having a first coating layer; and coating the catalyst precursor having the first coating layer with the second solution, and then performing a second heat treatment process to produce a catalyst having a second coating layer.

[0043] The coating method of the first solution and the second solution may be a method known in the art, such as, but not limited to, dip-coating, wash-coating, etc.

[0044] The first heat treatment step and the second heat treatment step may each independently include a drying step and a calcination step. The drying step may be performed at a temperature of 50°C to 150°C for 1 hour to 48 hours, or at a temperature of 60°C to 100°C for 5 hours to 36 hours, but is not limited thereto. The calcination step may be performed at a temperature of 350°C to 1,100°C for 1 hour to 10 hours in an air atmosphere, or at a temperature of 500°C to 1,000°C for 1.5 hours to 8 hours in an air atmosphere, but is not limited thereto. If the calcination step is performed at a temperature lower than 350°C, the perovskite phase may not be properly formed, and if it exceeds 1,100°C, the durability of the porous metal support may be reduced, which is not preferable.

[0045] In one embodiment of the present application, the method may further include a step of measuring the weight of the catalyst supported on the porous metal support after the second heat treatment step. Also, by measuring the weight of the catalyst supported on the porous metal support, the step of coating the porous metal support with the second solution and then performing the second heat treatment step may be repeated 1 to 10 times until a desired amount of catalyst is supported on the porous metal support.

[0046] In the methane reforming catalyst according to one embodiment of the present application, a first coating layer containing a perovskite-based compound represented by Chemical Formula 1 without a catalytic component is formed, which not only improves adhesion between the porous metal support and the second coating layer containing a perovskite-based compound represented by Chemical Formula 2, but also prevents side reactions of the porous metal support.

[0047] In addition, the methane reforming catalyst according to one embodiment of the present application has a perovskite-based compound supported on a porous metal support having high thermal conductivity, and therefore has the characteristic that the reaction heat can be easily controlled compared to conventional pellet-shaped or powder-shaped catalysts.

[0048] In addition, the catalyst for methane reforming according to one embodiment of the present application can increase the active surface area of the catalyst, so that it can exhibit high activity even at a high space velocity during the methane reforming reaction.

Examples

[0049] Hereinafter, in order to specifically describe the present application, examples will be given for detailed description. However, the examples according to the present application can be deformed into various different forms, and the scope of the present application is not construed as being limited to the examples described in detail below. The examples of the present application are provided to more fully explain the present application to those having average knowledge in the industry.

[0050] <Example> <Example 1> 1) Preparation of the first solution containing the precursor of the perovskite compound (SrTiO3) The perovskite compound component solution was prepared through the citric acid method. Strontium nitrate (Sr(NO3)3H2O) was dissolved in distilled water together with citric acid and ethylene glycol. Titanium isopropoxide (Ti(OCH(CH3)2)4) was dissolved in ethanol, and then the two solutions were mixed at 70°C. After stirring for 3 hours, it was cooled to room temperature and stored. At this time, the concentration of the above solution was 0.1M.

[0051] 2) Preparation of the second solution containing the precursor of the perovskite compound (SrTi 0.97 Ni 0.03 O 3-δ , 0 < δ < 1) The same procedure as in 1) above was carried out except that nickel nitrate (Ni(NO3)2) was used with an additional 3 mol% based on the metal relative to titanium.

[0052] 3) Preparation of the catalyst for methane reforming After dip-coating the above first solution on a porous metal support (NiCrAl, average pore size: 1,200 μm) to form the first coating layer, it was dried at 70°C for 24 hours, and then heat treatment was carried out at 300°C to 900°C in an air atmosphere for 3 hours.

[0053] Then, the second solution was dip-coated (formation of a second coating layer) on the porous metal support on which the first coating layer was formed, and then dried at 70°C for 24 hours and heat-treated at 300°C to 900°C in an air atmosphere for 3 hours. The dip-coating of the second solution, drying and heat-treatment were repeated several times to finally form a first coating layer (SrTiO3) and a second coating layer (SrTi 0.97 Ni 0.03 O 3-δ Based on the total weight of the methane reforming catalyst, the content of the perovskite-based compound (SrTiO3) was 7 wt %, and the perovskite-based compound (SrTi 0.97 Ni 0.03 O 3-δ , 0<δ<1) was 20% by weight.

[0054] An electron microscope photograph of the surface of the methane reforming catalyst according to Example 1 of the present application is shown in FIG.

[0055] The content of the perovskite-based compound represented by Formula 1 or 2 can be calculated by the following Formula 1. [Formula 1] Content (wt%) of the perovskite compound represented by Chemical Formula 1 or 2 = (total weight of catalyst - weight of porous metal support) / (total weight of catalyst) x 100

[0056] <Example 2> The second solution was produced in the same manner as in Example 1, except that yttrium nitrate (Y(NO3)2) was added in an amount of 12 mol% relative to strontium on a metal basis, and nickel nitrate (Ni(NO3)2) was added so that the molar ratio of titanium:nickel was 0.80:0.15.

[0057] <Example 3> The second solution was produced in the same manner as in Example 1, except that yttrium nitrate (Y(NO3)2) was added in an amount of 12 mol% relative to strontium on a metal basis, and nickel nitrate (Ni(NO3)2) was added so that the titanium:nickel molar ratio was 0.80:0.20.

[0058] <Example 4> The second solution was prepared in the same manner as in Example 1, except that ruthenium chloride (RuCl3) was added in an amount of 5 mol% based on titanium on a metal basis instead of nickel nitrate (Ni(NO3)2).

[0059] <Example 5> The second solution was produced in the same manner as in Example 1, except that yttrium nitrate (Y(NO3)2) was added in an amount of 8 mol% relative to strontium on a metal basis, and ruthenium chloride (RuCl3) was added so that the molar ratio of titanium:ruthenium was 0.80:0.15.

[0060] <Example 6> The same procedure as in Example 3 was carried out, except that the content of the perovskite compound (SrTiO3) was adjusted to 1.7 wt% based on the total weight of the methane reforming catalyst.

[0061] <Example 7> The same procedure as in Example 3 was carried out, except that the content of the perovskite compound (SrTiO3) was adjusted to 13 wt% based on the total weight of the methane reforming catalyst.

[0062] <Example 8> The same procedure as in Example 3 was carried out, except that the content of the perovskite compound (SrTiO3) was adjusted to 17 wt % based on the total weight of the methane reforming catalyst.

[0063] <Example 9> The same procedure as in Example 3 was carried out, except that NiFeCrAl (average pore size: 1,200 μm) was used as the porous metal support instead of NiCrAl.

[0064] <Example 10> The same procedure as in Example 3 was carried out, except that NiCrAl_800 (average pore size: 800 μm) was used as the porous metal support instead of NiCrAl.

[0065] <Example 11> The same procedure as in Example 3 was carried out, except that NiCrAl_1500 (average pore size: 1,500 μm) was used as the porous metal support instead of NiCrAl.

[0066] <Comparative Example 1> Only the porous metal support (NiCrAl, average pore size: 1,200 μm) was used as Comparative Example 1.

[0067] <Comparative Example 2> The same procedure as in Example 1 was carried out, except that the step of coating only the first solution was applied without the step of coating the second solution.

[0068] <Comparative Example 3> The same procedure as in Example 1 was carried out, except that the step of coating only the second solution was applied without the step of coating the first solution.

[0069] <Comparative Example 4> The same procedure as in Example 3 was carried out, except that the step of coating only the second solution was applied without the step of coating the first solution.

[0070] The configurations of the porous metal support, the first coating layer and the second coating layer in the above examples and comparative examples are shown in Table 1 below.

[0071] [Table 1]

[0072] <Experimental Example 1> Evaluation of Dry Reforming Reaction of Methane To carry out the dry reforming reaction of methane, a fixed-bed reaction system was introduced. A quartz tube reactor (inner diameter = 1 / 2 inch, length = 50 cm) was used and filled with each catalyst (about 2 g) of the examples and comparative examples. First, after undergoing a reduction process at 800 °C for 1 to 2 hours under the condition of 10% H2 / N2, the catalytic reaction proceeded for 100 hours. To more clearly compare the differences in activity between the catalysts, the activity characteristics of the catalysts were evaluated at a severe space velocity. Gas composition: CH4:CO2:N2 = 1:1.2:0.96 Flow rate: GHSV (Gas Hour Space Velocity) = 2,500 hr -1 (Based on CH4) Reaction temperature: 750 °C Reaction pressure: 1 bar

[0073] The product gas composition was analyzed using gas chromatography (GC), and the reaction conversion rate after 100 hours of reaction was calculated and shown in Table 2 below. Conversion rate (Xi, %) = [(Fi in - Fi out ) / Fi in × 100 (Fi = flow rate of i) <GC Analysis Conditions> 1) GC model: Agilent 6890 2) Oven temperature: 40 °C / 7 min - 90 °C / 5 min - 180 °C / 6 min 3) Detector: TCD, 250 °C 4) Sample loop: 0.25 mL 5) Valve box temperature: 150 °C

[0074]

Table 2

[0075] <Experimental Example 2> Evaluation of Dry Reforming Reaction of Methane To perform the dry reforming reaction of methane, a fixed-bed reaction system was introduced. A quartz tube reactor (inner diameter = 1 / 2 inch, length = 50 cm) was used and filled with each catalyst (about 2 g) of the examples and comparative examples. First, after undergoing a reduction process at 800 °C for 1 to 2 hours under the condition of 10% H2 / N2, the catalytic reaction was allowed to proceed for 100 hours. To more clearly compare the differences in activity between the catalysts, the activity characteristics of the catalysts were evaluated at a severe space velocity. Gas composition: CH4:CO2:N2 = 1:1.2:0.96 Flow rate: GHSV (Gas Hour Space Velocity) = 1,500 hr -1 (Based on CH4) Reaction temperature: 800 °C Reaction pressure: 1 bar

[0076] The composition of the product gas was analyzed using gas chromatography (GC), and the reaction conversion rate after 100 hours of reaction was calculated and shown in Table 3 below. Conversion rate (Xi, %) = [(Fi in - Fi out ) / Fi in × 100 (Fi = flow rate of i) <GC analysis conditions> 1) GC model: Agilent 6890 2) Oven temperature: 40 °C / 7 min - 90 °C / 5 min - 180 °C / 6 min 3) Detector: TCD, 250 °C 4) Sample loop: 0.25 mL 5) Valve box temperature: 150℃

[0077] [Table 3]

[0078] As shown in the results of Table 3, when Example 3 and Comparative Example 4 are compared with each other, it can be seen that the methane reforming catalyst including the porous metal support according to the present invention, the first coating layer including the perovskite-based compound represented by Chemical Formula 1, and the second coating layer including the perovskite-based compound represented by Chemical Formula 2 has superior CH4 conversion rate and CO2 conversion rate compared to Comparative Example 4 in which the first coating layer is not applied.

[0079] As shown in the above results, it can be confirmed that the H2 / CO ratio can be improved in the examples of the present application compared to the comparative examples, and therefore, it can be confirmed that the side reactions caused by the porous metal support are reduced in the examples of the present application.

[0080] Therefore, in the methane reforming catalyst according to one embodiment of the present application, by forming a first coating layer containing a perovskite-based compound represented by Chemical Formula 1 without a catalytic component, it is possible to not only improve the adhesion between the porous metal support and the second coating layer containing a perovskite-based compound represented by Chemical Formula 2, but also to prevent side reactions of the porous metal support.

[0081] In addition, the methane reforming catalyst according to one embodiment of the present application has a perovskite-based compound supported on a porous metal support having high thermal conductivity, and therefore has the characteristic that the reaction heat can be easily controlled compared to conventional pellet-shaped or powder-shaped catalysts.

[0082] In addition, the methane reforming catalyst according to one embodiment of the present application can increase the active surface area of ​​the catalyst, and therefore can exhibit high activity even at a high space velocity during the methane reforming reaction.

Claims

1. porous metal support; a first coating layer provided on the porous metal support and including a perovskite-based compound represented by the following Chemical Formula 1; and A second coating layer provided on the first coating layer, the second coating layer comprising a perovskite-based compound represented by the following chemical formula 3 or 4: A catalyst for methane reforming comprising: [Chemical formula 1] SrTiO ３ [Chemical formula 3] SrTi α B y O 3-δ [Chemical formula 4] Sr 1-x Y x Ti α B y O 3-δ In the above Chemical Formulas 3 and 4, B is Ni or Ru; x is a real number greater than 0 and less than 1, y is a real number greater than 0 and less than 0.3; δ is a real number greater than 0 and less than 1, α is a real number greater than 0.7 and equal to or less than 1.

2. 2. The methane reforming catalyst of claim 1, wherein the porous metal support is a metal foam comprising NiFeCrAl or NiCrAl.

3. The methane reforming catalyst according to claim 1, wherein the content of the perovskite-based compound represented by Formula 3 or 4 is 3 wt % to 40 wt % based on the total weight of the methane reforming catalyst.

4. Steam reforming, carbon dioxide reforming 2 2. The methane reforming catalyst according to claim 1, which is applied to a methane reforming process, a catalytic partial oxidation process, an autothermal reforming process, a tri-reforming process or a mixed reforming process.

5. Preparing a first solution containing a precursor of a perovskite-based compound represented by the following Chemical Formula 1; and preparing a second solution containing a precursor of a perovskite-based compound represented by the following Chemical Formula 3 or 4: A step of coating a porous metal support with the first solution and then carrying out a first heat treatment process to prepare a catalyst precursor having a first coating layer; and and coating the catalyst precursor having the first coating layer with the second solution, and then performing a second heat treatment process to prepare a catalyst having a second coating layer. A method for producing a catalyst for methane reforming, comprising: [Chemical formula 1] SrTiO ３ [Chemical formula 3] SrTi α B y O 3-δ [Chemical formula 4] Sr 1-x Y x Ti α B y O 3-δ In the above Chemical Formulas 3 and 4, B is Ni or Ru; x is a real number greater than 0 and less than 1, y is a real number greater than 0 and less than 0.3; δ is a real number greater than 0 and less than 1, α is a real number greater than 0.7 and equal to or less than 1.

6. 6. The method for preparing a methane reforming catalyst according to claim 5, wherein the porous metal support is a metal foam comprising NiFeCrAl or NiCrAl.

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