Catalyst for reforming of methane and method for manufacturing thereof

Abstract

A catalyst for methane reforming according to one embodiment of the present application comprises a porous metal support; perovskite-based catalyst particles supported on the porous metal support; and a perovskite-based binder supported on the porous metal support, wherein the perovskite-based catalyst particles and the perovskite-based binder each independently comprise a compound represented by Formula 1.

Description

Technology Field

[0001] This application claims the benefit of the filing date of Korean Patent Application No. 10-2021-0158414 filed with the Korean Intellectual Property Office on November 17, 2021, the entire contents of which are incorporated herein.

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

[0003] Extensive research on carbon dioxide conversion technologies is currently underway as part of efforts to reduce greenhouse gas emissions caused by global warming. One such technology, carbon dioxide reforming, is a process that produces synthesis gas composed of hydrogen and carbon monoxide by reacting methane with carbon dioxide.

[0004] Syngas is a material with high development value as a raw material for various downstream processes. As a method to industrially obtain synthesis gas (H2 / CO), natural gas reforming reactions can be broadly classified into steam reforming, CO2 reforming, catalytic partial oxidation, autothermal reforming, and tri-reforming, as shown in reaction equations 1 to 5 below.

[0005] [Reaction Equation 1]

[0006] CH4+ H2O → 3H2+ CO △H = 226 kJ / mol

[0007] [Reaction Equation 2]

[0008] CH4+ CO2→ 2H2+ 2CO △H = 261 kJ / mol

[0009] [Reaction Equation 3]

[0010] CH4+ 0.5O2→ 2H2+ CO △H = -44 kJ / mol

[0011] [Reaction Equation 4]

[0012] autothermal reforming: Equation 1 + Equation 3

[0013] [Reaction Equation 5]

[0014] tri-reforming: Equation 1 + Equation 2 + Equation 3

[0015] Meanwhile, various catalysts may be used in the above-mentioned reforming process to enhance reforming activity. Among these, using precious metal catalysts in the reforming process offers the advantage of high hydrogen conversion efficiency from biogas; however, due to the high cost of precious metal catalysts, there is a problem of reduced economic feasibility.

[0016] Accordingly, nickel catalysts, which have high hydrogen conversion efficiency and are relatively inexpensive, are primarily used in the reforming process. However, in such cases, there is a problem in that the nickel catalyst is deactivated by carbon inevitably generated on its surface.

[0017] Therefore, in this technical field, there is a need for the development of catalysts that are resistant to carbon deposition and can be effectively applied to the methane reforming process. Prior art literature

[0018] Republic of Korea Published Patent Application No. 10-2019-0076367 The problem to be solved

[0019] The present application aims to provide a catalyst for methane reforming and a method for manufacturing the same. means of solving the problem

[0020] One embodiment of the present application is,

[0021] porous metal support;

[0022] Perovskite-based catalyst particles supported on the above-mentioned porous metal support; and

[0023] It comprises a perovskite-based binder supported on the above-mentioned porous metal support, and

[0024] The present invention provides a catalyst for methane reforming in which the perovskite-based catalyst particles and the perovskite-based binder each independently comprise a compound represented by the following chemical formula 1.

[0025] [Chemical Formula 1]

[0026] Sr 1-x A x Ti 1-y B y O 3-δ

[0027] In the above chemical formula 1,

[0028] A is Y, La, or Ba, and

[0029] B is Ni, Co, Fe, Mn, Cr, Mo, Ru, or Rh, and

[0030] x is a real number greater than or equal to 0 and less than 1, and

[0031] y is a real number greater than or equal to 0 and less than 0.5, and

[0032] δ is a real number greater than 0 and less than 1, and

[0033] It satisfies x + y > 0.

[0034] In addition, other embodiments of the present application are,

[0035] A step of preparing a slurry by mixing perovskite-based catalyst particles and a perovskite-based catalyst sol;

[0036] A step of impregnating a porous metal support into the slurry; and

[0037] It includes drying and firing steps,

[0038] The present invention provides a method for manufacturing a catalyst for methane reforming in which the perovskite-based catalyst particles and the perovskite-based catalyst sol each independently comprise a compound represented by the chemical formula 1. Effects of the invention

[0039] A catalyst for methane reforming according to one embodiment of the present application is prepared by mixing a catalyst sol of the same or similar series as the catalyst particles with an inorganic binder to form a slurry, and then coating this slurry onto a metal support with high thermal conductivity. This allows for an increase in the amount of catalyst supported at once and suppresses side reactions caused by the binder.

[0040] In addition, the catalyst for methane reforming according to one embodiment of the present application has the characteristic that reaction heat control is easy compared to conventional pellet-type or powder-type catalysts, as catalyst particles and a binder are supported on a porous metal support with high thermal conductivity. Brief explanation of the drawing

[0041] Figure 1 is an electron microscope image of the surface of a methane reforming catalyst according to Example 1 of the present application. Specific details for implementing the invention

[0042] The present specification will be described in more detail below.

[0043] In this specification, when it is said that a member is located "on" another member, this includes not only cases where a member is in contact with another member, but also cases where another member exists between the two members.

[0044] In this specification, when a part is described as "comprising" a certain component, it means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0045] Currently, the catalysts widely used in the field of reformers generally consist of powder catalysts and pellet-supported catalysts. While powder catalysts offer excellent performance due to their superior dispersion, they present difficulties in direct industrial applications. For instance, when a reformer is operated using a powder catalyst, the catalyst is expelled along with the substances produced after the reaction. Consequently, the powder catalyst can gradually accumulate in the outlet tube, eventually blocking the entire tube. Therefore, there is a disadvantage in that powder catalysts cannot be used in commercially available reformers used in industry.

[0046] In addition, the aforementioned pellet-type support catalyst is currently widely used in industrial reformers. Although its performance is inferior to that of powder-type catalysts in terms of catalytic performance alone due to limitations in mass transfer rate, it has the advantage of being usable for a long time because it utilizes a support. However, γ-Al2O3 pellets, which are commonly used as the pellet-type support catalyst, have the disadvantage of being prone to breakage due to their weak structural strength, which causes a pressure difference within the reactor. Furthermore, due to the characteristics of the pellet-type support catalyst, it has a large volume, so its size increases significantly when used in high-capacity reformers. Additionally, all reforming reactions are sensitive to reaction temperature, but conventional pellet-type catalysts have the disadvantage of having very low thermal conductivity, resulting in uneven heat distribution throughout the reactor.

[0047] Accordingly, the present application aims to improve the heat and mass transfer rate, which is a common disadvantage of both powder and pellet types, as well as the phenomenon of clogging the ducts, which is a disadvantage of the powder type, by coating a catalyst onto a porous metal support having a high heat and mass transfer rate.

[0048] The porous metal support catalyst described above can be prepared by coating a slurry, prepared by mixing a catalyst precursor or catalyst powder with a binder, additives, etc., onto the surface of a porous metal support. To introduce catalyst particles onto the surface of the porous metal support, an organic binder and / or an inorganic binder may be added during the preparation of the slurry. The organic binder remains in the slurry until the drying and calcination processes and can contribute to reducing surface tension and stabilizing the slurry. The inorganic binder remains between catalyst particles or between catalyst particles and the porous metal support after the calcination process and serves to fix the catalyst particles onto the porous metal support; it can mainly be added in the form of silica, alumina sol, or colloid. While using a large amount of the inorganic binder has the advantage of strengthening the bond between the catalyst particles and the porous metal support, on the other hand, the presence of a large amount of binder on the surface of the catalyst particles may reduce the number of reaction sites, the binder may affect the catalyst, and it may simultaneously participate in the reaction to induce unwanted side reactions. Accordingly, there are cases where catalyst precursors are used directly to introduce the catalyst into a porous metal support without a binder, but this has the disadvantage that the amount of catalyst supported at once is small.

[0049] Accordingly, the present application aims to provide a catalyst for methane reforming that allows for a large amount of catalyst to be supported at once while also suppressing side reactions caused by the binder.

[0050] A catalyst for methane reforming according to one embodiment of the present application comprises: a porous metal support; perovskite-based catalyst particles supported on the porous metal support; and a perovskite-based binder supported on the porous metal support.

[0051] In one embodiment of the present application, the perovskite-based catalyst particles and the perovskite-based binder may each independently comprise a compound represented by the following chemical formula 1.

[0052] [Chemical Formula 1]

[0053] Sr 1-x A x Ti 1-y B y O 3-δ

[0054] In the above chemical formula 1,

[0055] A is Y, La, or Ba, and

[0056] B is Ni, Co, Fe, Mn, Cr, Mo, Ru, or Rh, and

[0057] x is a real number greater than or equal to 0 and less than 1, and

[0058] y is a real number greater than or equal to 0 and less than 0.5, and

[0059] δ is a real number greater than 0 and less than 1, and

[0060] It satisfies x + y > 0.

[0061] In one embodiment of the present application, the perovskite-based catalyst particles and the perovskite-based binder may comprise the same compound or different compounds. Accordingly, in one embodiment of the present application, the methane reforming catalyst may comprise two different types of perovskite-based compounds.

[0062] In one embodiment of the present application, the formula 1 may be represented by any one of the following formulas 2 to 4.

[0063] [Chemical Formula 2]

[0064] SrTi 1-y B y O 3-δ

[0065] [Chemical Formula 3]

[0066] Sr 1-x Y x TiO 3-δ

[0067] [Chemical Formula 4]

[0068] Sr1-x Y x Ti 1-y B y O 3-δ

[0069] In the above chemical formulas 2 to 4,

[0070] B is Ni or Ru, and

[0071] x is a real number greater than 0 and less than 1, and

[0072] y is a real number greater than 0 and less than 0.5, and

[0073] δ is a real number greater than 0 and less than 1.

[0074] In one embodiment of the present application, the porous metal support may be composed of a material capable of maintaining thermal stability at a high temperature of 800°C or higher.

[0075] In one embodiment of the present application, the porous metal support may be composed of one or more materials selected from NiFeCrAl, NiCrAl, SiC, Al, stainless steel, and Inconel.

[0076] The porous metal support described above is a support having various shapes, and since it has a low heat capacity and excellent heat transfer ability, it can be molded 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%, preferably 50% to 99%. In addition, the average pore size of the porous metal support may be 150㎛ to 4,000㎛, 200㎛ to 3,500㎛, or 400㎛ to 3,000㎛. The porous metal support may be appropriately manufactured by a person skilled in the art using methods known in the art, taking into account the material, pore size, and porosity of the porous metal support described above. According to one embodiment of the present application, a porous metal support having various materials, pore sizes, etc., as described in the examples below may be applied.

[0077] In one embodiment of the present application, based on the total weight of the methane reforming catalyst, the total content of the perovskite-based catalyst particles and the perovskite-based binder may be 3% to 40% by weight, 6% to 35% by weight, or 7% to 30% by weight. If the total content of the perovskite-based catalyst particles and the perovskite-based binder is less than 3% by weight 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, making it impossible to achieve the desired catalyst performance. Furthermore, if the total content of the perovskite-based catalyst particles and the perovskite-based binder exceeds 40% by weight, it contains a relatively large amount of catalyst components relative to the porous metal support, which may clog the pores and cause a differential pressure, thereby reducing the practical benefits of the methane reforming reaction.

[0078] In one embodiment of the present application, at least a portion of the surface of the catalyst particle may include a protrusion shape. The protrusion shape may be spherical, elliptical, or a combination thereof, but is not limited thereto. The average diameter of each of the protrusions may be 20 nm to 1 µm. The protrusions may cover the entire surface of the catalyst particle or may cover only a portion of the surface of the catalyst particle.

[0079] In one embodiment of the present application, the perovskite-based binder is an inorganic binder and can serve to fix the perovskite-based catalyst particles onto a porous metal support. Additionally, the perovskite-based binder may exist in a protruding shape on the perovskite-based catalyst particles, thereby increasing the reaction surface area of ​​the catalyst and improving the performance of the methane reforming reaction.

[0080] In addition, according to one embodiment of the present application, by additionally applying a perovskite-based binder in addition to the perovskite-based catalyst particles, the amount of catalyst supported on a porous metal support in a single coating can be increased compared to when the catalyst particles are applied alone. In addition, by applying the perovskite-based binder according to one embodiment of the present application, side reactions or catalyst phase changes that may occur when silica or other colloidal inorganic binders are applied can be prevented, thereby improving the performance of the methane reforming reaction.

[0081] In one embodiment of the present application, the methane reforming catalyst may be applied to a steam reforming process, a CO2 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.

[0082] A method for manufacturing a catalyst for methane reforming according to one embodiment of the present application comprises the steps of: mixing perovskite-based catalyst particles and perovskite-based catalyst sol to prepare a slurry; impregnating a porous metal support into the slurry; and drying and calcining, wherein the perovskite-based catalyst particles and the perovskite-based catalyst sol each independently comprise a compound represented by Chemical Formula 1.

[0083] In the method for manufacturing a catalyst for methane reforming according to one embodiment of the present application, the details regarding the porous metal support, perovskite-based catalyst particles, etc. are the same as those described above.

[0084] In particular, the perovskite-based binder of the above-mentioned methane reforming catalyst can be formed from the above-mentioned perovskite-based catalyst sol.

[0085] The above perovskite catalyst sol can be formed from a solution containing a precursor of a perovskite compound and a solvent. The precursor of the perovskite compound is a precursor of the metal constituting the perovskite compound, and the molar ratio of the metal in the perovskite compound can be controlled by adjusting its content. Furthermore, there are no particular limitations on the metal precursor, and a combination of ammonium salts, nitrates, carbonates, chlorides, sulfates, hydroxides, organic acid salts, oxides, or mixtures thereof of the metal element may be used. The solvent is not particularly limited and any solvent known in the art may be used. For example, water, alcohol-based solvents, etc., may be used as the solvent, but are not limited thereto.

[0086] A method for manufacturing a catalyst for methane reforming according to one embodiment of the present application includes the step of preparing a slurry by mixing perovskite-based catalyst particles and a perovskite-based catalyst sol. At this time, the solvent may be additionally added to control the concentration of the slurry.

[0087] A method for manufacturing a catalyst for methane reforming according to one embodiment of the present application includes the step of impregnating a porous metal support with the slurry. At this time, the method may further include the step of removing excess slurry from the porous metal support.

[0088] A method for manufacturing a catalyst for methane reforming according to one embodiment of the present application comprises, after the step of impregnating the porous metal support with the slurry, a step of drying and calcining. The drying may be performed at a temperature of 50°C to 100°C for 20 minutes to 2 hours, and at a temperature of 60°C to 90°C for 30 minutes to 1.5 hours, but is not limited thereto. Additionally, the calcination may be performed at a temperature of 350°C to 1,100°C for 1 hour to 15 hours under an air atmosphere, and at a temperature of 500°C to 1,000°C for 3 hours to 10 hours under an air atmosphere, but is not limited thereto. If the calcination is performed for less than 1 hour, the perovskite-based sol applied as a binder is not suitable for forming a crystalline phase, and if the calcination is performed for more than 15 hours, it is undesirable in terms of energy consumption.

[0089] In one embodiment of the present application, the step of measuring the weight of the catalyst supported on the porous metal support after the drying and calcining step may be further included. Additionally, by measuring the weight of the catalyst supported on the porous metal support, the step of impregnating the aforementioned porous metal support into the slurry until a desired amount of catalyst is supported on the porous metal support; and the drying and calcining step may be repeated 1 to 20 times.

[0090] A catalyst for methane reforming according to one embodiment of the present application is prepared by mixing a catalyst sol of the same or similar series as the catalyst particles with an inorganic binder to form a slurry, and then coating this slurry onto a metal support with high thermal conductivity. This allows for an increase in the amount of catalyst supported at once and suppresses side reactions caused by the binder.

[0091] In addition, the catalyst for methane reforming according to one embodiment of the present application has the characteristic that reaction heat control is easy compared to conventional pellet-type or powder-type catalysts, as catalyst particles and a binder are supported on a porous metal support with high thermal conductivity.

[0092] Hereinafter, the present application will be described in detail with reference to examples to specifically explain the present application. However, the embodiments according to the present application may be modified in various different forms, and the scope of the present application is not to be interpreted as being limited to the embodiments described below. The embodiments of the present application are provided to more completely explain the present application to those with average knowledge in the art.

[0093] <Example>

[0094] <Comparative Example 1>

[0095] 1) Perovskite catalyst (SrTiO2 3 Preparation of sol

[0096] A perovskite catalyst (SrTiO3) sol was prepared using the citric acid method. Strontium nitrate (Sr(NO3)3H2O) was dissolved in distilled water along with citric acid and ethylene glycol. Titanium isopropoxide (Ti(OCH(CH3)2)4) was dissolved in ethanol, and the two solutions were mixed at 70°C. Afterward, the mixture was stirred for 3 hours, cooled to room temperature, and stored.

[0097] 2) Perovskite catalyst particles (SrTi 0.995 Ni 0.005 O 3-δ Manufacture of , 0 < δ < 1)

[0098] The procedure was performed in the same manner as in 1) above, except that 0.5 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium.

[0099] The solution prepared in this way was placed in a crucible, dried at 150°C for 24 hours, and calcined at 900°C to produce perovskite catalyst particles.

[0100] 3) Preparation of catalyst for methane reforming

[0101] A slurry was prepared by mixing the perovskite catalyst particles and the perovskite catalyst sol prepared above. At this time, the content of the perovskite catalyst particles was 5 wt%, the concentration of the perovskite catalyst sol was 0.1 M, and water was used as the solvent.

[0102] A porous metal support (NiFeCrAl, average pore size: 800 μm) was impregnated into the above slurry for 1 minute, and excess slurry was removed from the porous metal support using a blower. Afterward, the material was dried at 70°C for 1 hour, and then heat-treated at 900°C for 5 hours under an air atmosphere to produce a methane reforming catalyst coated with perovskite catalyst particles and a perovskite binder on a porous metal support. This process was repeated several times to finally produce a methane reforming catalyst.

[0103] <Example 1>

[0104] 1) Perovskite catalyst (Sr 0.95 Y 0.05 Ti 0.97 Ru 0.03 O 3-δ , 0 < δ < 1) Preparation of a sol

[0105] The procedure was performed in the same manner as in Comparative Example 1 of the above, except that 3 mol% of ruthenium chloride (RuCl3) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0106] 2) Perovskite catalyst particles (Sr 0.85 Y 0.15 Ti 0.95 Ru 0.05 O 3-δ Manufacture of , 0 < δ < 1)

[0107] The procedure was performed in the same manner as in Comparative Example 1), except that 5 mol% of ruthenium chloride (RuCl3) was added relative to titanium and 15 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0108] The solution prepared in this way was placed in a crucible, dried at 150°C for 24 hours, and calcined at 900°C to produce perovskite catalyst particles.

[0109] 3) Preparation of catalyst for methane reforming

[0110] A slurry was prepared by mixing the perovskite catalyst particles and perovskite catalyst sol prepared in Example 1 above, and the procedure was carried out in the same manner as 3) of Comparative Example 1 above, except that NiFeCrAl (average pore size: 400 μm) was applied as a porous metal support.

[0111] <Example 2>

[0112] 1) Perovskite catalyst (SrTi 0.97 Ni 0.03 O 3-δ , 0 < δ < 1) Preparation of a sol

[0113] The procedure was performed in the same manner as 1) of Comparative Example 1 above, except that 3 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium.

[0114] 2) Perovskite catalyst particles (SrTi 0.95 Ni 0.05 O 3-δ Manufacture of , 0 < δ < 1)

[0115] The procedure was performed in the same manner as 1) of Comparative Example 1 above, except that 5 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium.

[0116] The solution prepared in this way was placed in a crucible, dried at 150°C for 24 hours, and calcined at 900°C to produce perovskite catalyst particles.

[0117] 3) Preparation of catalyst for methane reforming

[0118] Except for preparing a slurry by mixing the perovskite catalyst particles prepared in Example 2 above and the perovskite catalyst sol, the procedure was carried out in the same manner as 3) of Comparative Example 1 above.

[0119] <Example 3>

[0120] 1) Perovskite catalyst (Sr 0.95 Y 0.05 Ti 0.97 Ru 0.03 O 3-δ , 0 < δ < 1) Preparation of a sol

[0121] The procedure was performed in the same manner as in Comparative Example 1 of the above, except that 3 mol% of ruthenium chloride (RuCl3) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0122] 2) Perovskite catalyst particles (Sr 0.95 Y 0.05 Ti 0.90 Ni 0.10 O 3-δ Manufacture of , 0 < δ < 1)

[0123] The procedure was performed in the same manner as in Comparative Example 1), except that 10 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0124] The solution prepared in this way was placed in a crucible, dried at 150°C for 24 hours, and calcined at 900°C to produce perovskite catalyst particles.

[0125] 3) Preparation of catalyst for methane reforming

[0126] The procedure was performed in the same manner as 3) of Comparative Example 1, except that a slurry was prepared by mixing the perovskite catalyst particles prepared in Example 3 and the perovskite catalyst sol.

[0127] <Example 4>

[0128] 1) Perovskite catalyst (SrTi 0.97 Ru 0.03 O 3-δ , 0 < δ < 1) Preparation of a sol

[0129] The procedure was performed in the same manner as 1) of Comparative Example 1 above, except that 3 mol% of ruthenium chloride (RuCl3) was added relative to titanium.

[0130] 2) Perovskite catalyst particles (SrTi 0.93 Ni 0.07 O 3-δ Manufacture of , 0 < δ < 1)

[0131] The procedure was performed in the same manner as 1) of Comparative Example 1 above, except that 7 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium.

[0132] The solution prepared in this way was placed in a crucible, dried at 150°C for 24 hours, and calcined at 900°C to produce perovskite catalyst particles.

[0133] 3) Preparation of catalyst for methane reforming

[0134] A slurry was prepared by mixing the perovskite catalyst particles and perovskite catalyst sol prepared in Example 4 above, and the procedure was carried out in the same manner as 3) of Comparative Example 1 above, except that NiFeCrAl (average pore size: 1,200 μm) was applied as a porous metal support.

[0135] <Example 5>

[0136] 1) Perovskite catalyst (Sr 0.95 Y 0.05 Ti 0.93 Ni 0.07 O 3-δ , 0 < δ < 1) Preparation of a sol

[0137] The procedure was performed in the same manner as in Comparative Example 1), except that 7 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0138] 2) Perovskite catalyst particles (Sr 0.95 Y 0.05 Ti 0.93 Ni 0.07 O 3-δ Manufacture of , 0 < δ < 1)

[0139] The procedure was performed in the same manner as in Comparative Example 1), except that 7 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0140] The solution prepared in this way was placed in a crucible, dried at 150°C for 24 hours, and calcined at 900°C to produce perovskite catalyst particles.

[0141] 3) Preparation of catalyst for methane reforming

[0142] A slurry was prepared by mixing the perovskite catalyst particles and perovskite catalyst sol prepared in Example 5 above, and the procedure was carried out in the same manner as 3) of Comparative Example 1 above, except that NiFeCrAl (average pore size: 1,200 μm) was applied as a porous metal support.

[0143] <Example 6>

[0144] 1) Perovskite catalyst (Sr 0.95 Y 0.05 Ti 0.85 Ru 0.15 O 3-δ , 0 < δ < 1) Preparation of a sol

[0145] The procedure was carried out in the same manner as in Comparative Example 1), except that 15 mol% of ruthenium chloride (RuCl3) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0146] 2) Perovskite catalyst particles (Sr 0.95 Y 0.05 Ti 0.80 Ni 0.20 O 3-δ Manufacture of , 0 < δ < 1)

[0147] The procedure was performed in the same manner as in Comparative Example 1), except that 20 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0148] The solution prepared in this way was placed in a crucible, dried at 150°C for 24 hours, and calcined at 900°C to produce perovskite catalyst particles.

[0149] 3) Preparation of catalyst for methane reforming

[0150] A slurry was prepared by mixing the perovskite catalyst particles and perovskite catalyst sol prepared in Example 6 above, and the procedure was carried out in the same manner as 3) of Comparative Example 1 above, except that NiFeCrAl (average pore size: 3,000 μm) was applied as a porous metal support.

[0151] <Example 7>

[0152] 1) Perovskite catalyst (Sr 0.95 Y 0.05 Ti 0.90 Ru 0.10 O 3-δ , 0 < δ < 1) Preparation of a sol

[0153] The procedure was carried out in the same manner as in Comparative Example 1), except that 10 mol% of ruthenium chloride (RuCl3) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0154] 2) Perovskite catalyst particles (Sr 0.95 Y 0.05 Ti 0.80 Ni 0.20 O 3-δ Manufacture of , 0 < δ < 1)

[0155] The procedure was performed in the same manner as in Comparative Example 1), except that 20 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0156] The solution prepared in this way was placed in a crucible, dried at 150°C for 24 hours, and calcined at 900°C to produce perovskite catalyst particles.

[0157] 3) Preparation of catalyst for methane reforming

[0158] A slurry was prepared by mixing the perovskite catalyst particles and perovskite catalyst sol prepared in Example 7 above, and the procedure was carried out in the same manner as 3) of Comparative Example 1 above, except that NiFeCrAl (average pore size: 3,000 μm) was applied as a porous metal support.

[0159] <Example 8>

[0160] 1) Perovskite catalyst (SrTi 0.97 Ni 0.03 O 3-δ , 0 < δ < 1) Preparation of a sol

[0161] The procedure was performed in the same manner as 1) of Comparative Example 1 above, except that 3 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium.

[0162] 2) Perovskite catalyst particles (SrTi 0.97 Ni 0.03 O 3-δ Manufacture of , 0 < δ < 1)

[0163] The procedure was performed in the same manner as 1) of Comparative Example 1 above, except that 3 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium.

[0164] The solution prepared in this way was placed in a crucible, dried at 150°C for 24 hours, and calcined at 900°C to produce perovskite catalyst particles.

[0165] 3) Preparation of catalyst for methane reforming

[0166] A slurry was prepared by mixing the perovskite catalyst particles and perovskite catalyst sol prepared in Example 8 above, and the procedure was carried out in the same manner as 3) of Comparative Example 1 above, except that NiCrAl (average pore size: 400 μm) was applied as a porous metal support.

[0167] <Example 9>

[0168] 1) Perovskite catalyst (Sr 0.95 Y 0.05 Ti 0.97 Ni 0.03 O 3-δ , 0 < δ < 1) Preparation of a sol

[0169] The procedure was performed in the same manner as in Comparative Example 1), except that 3 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0170] 2) Perovskite catalyst particles (Sr 0.95 Y 0.05 Ti 0.97 Ni 0.03 O 3-δ Manufacture of , 0 < δ < 1)

[0171] The procedure was performed in the same manner as in Comparative Example 1), except that 3 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0172] The solution prepared in this way was placed in a crucible, dried at 150°C for 24 hours, and calcined at 900°C to produce perovskite catalyst particles.

[0173] 3) Preparation of catalyst for methane reforming

[0174] A slurry was prepared by mixing the perovskite catalyst particles and perovskite catalyst sol prepared in Example 9 above, and the procedure was carried out in the same manner as 3) of Comparative Example 1 above, except that NiCrAl (average pore size: 800 μm) was applied as a porous metal support.

[0175] <Example 10>

[0176] 1) Perovskite catalyst (Sr 0.95 Y 0.05 Ti 0.97 Ru 0.03 O 3-δ , 0 < δ < 1) Preparation of a sol

[0177] The procedure was performed in the same manner as in Comparative Example 1 of the above, except that 3 mol% of ruthenium chloride (RuCl3) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0178] 2) Perovskite catalyst particles (SrTi 0.90 Ni 0.10 O 3-δ Manufacture of , 0 < δ < 1)

[0179] The procedure was performed in the same manner as 1) of Comparative Example 1 above, except that nickel nitrate (Ni(NO3)2) was added at 10 mol% relative to titanium.

[0180] The solution prepared in this way was placed in a crucible, dried at 150°C for 24 hours, and calcined at 900°C to produce perovskite catalyst particles.

[0181] 3) Preparation of catalyst for methane reforming

[0182] A slurry was prepared by mixing the perovskite catalyst particles and perovskite catalyst sol prepared in Example 10 above, and the procedure was carried out in the same manner as 3) of Comparative Example 1 above, except that NiCrAl (average pore size: 1,200 μm) was applied as a porous metal support.

[0183] <Example 11>

[0184] 1) Perovskite catalyst (Sr 0.95 Y 0.05 Ti 0.90 Ru 0.10 O 3-δ , 0 < δ < 1) Preparation of a sol

[0185] The procedure was carried out in the same manner as in Comparative Example 1), except that 10 mol% of ruthenium chloride (RuCl3) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0186] 2) Perovskite catalyst particles (Sr 0.95 Y 0.05 Ti 0.80 Ni 0.20 O 3-δ Manufacture of , 0 < δ < 1)

[0187] The procedure was performed in the same manner as in Comparative Example 1), except that 20 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium and 5 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0188] The solution prepared in this way was placed in a crucible, dried at 150°C for 24 hours, and calcined at 900°C to produce perovskite catalyst particles.

[0189] 3) Preparation of catalyst for methane reforming

[0190] A slurry was prepared by mixing the perovskite catalyst particles and perovskite catalyst sol prepared in Example 11 above, and the procedure was carried out in the same manner as 3) of Comparative Example 1 above, except that NiCrAl (average pore size: 1,500 μm) was applied as a porous metal support.

[0191] <Example 12>

[0192] 1) Perovskite catalyst (Sr 0.85 Y 0.15 Ti 0.97 Ni 0.03 O 3-δ , 0 < δ < 1) Preparation of a sol

[0193] The procedure was performed in the same manner as in Comparative Example 1), except that 3 mol% of nickel nitrate (Ni(NO3)2) was added relative to titanium and 15 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0194] 2) Perovskite catalyst particles (Sr 0.85 Y 0.15 Ti 0.97 Ru 0.03 O 3-δ δ Manufacture of , 0 < δ < 1)

[0195] The procedure was carried out in the same manner as in Comparative Example 1), except that 3 mol% of ruthenium chloride (RuCl3) was added relative to titanium and 15 mol% of yttrium nitrate (Y(NO3)2) was added relative to strontium.

[0196] The solution prepared in this way was placed in a crucible, dried at 150°C for 24 hours, and calcined at 900°C to produce perovskite catalyst particles.

[0197] 3) Preparation of catalyst for methane reforming

[0198] A slurry was prepared by mixing the perovskite catalyst particles and perovskite catalyst sol prepared in Example 12 above, and the procedure was carried out in the same manner as 3) of Comparative Example 1 above, except that NiCrAl (average pore size: 3,000 μm) was applied as a porous metal support.

[0199] <Comparative Example 2>

[0200] A catalyst was prepared in the same manner as in Example 8, except that an inorganic binder, SiO2(Ludox), was used instead of a perovskite catalyst sol, and NiCrAl (average pore size: 1,200 μm) was used as a porous metal support.

[0201] <Comparative Example 3>

[0202] A catalyst was prepared in the same manner as in Example 2 above, except that perovskite catalyst particles were not applied, a perovskite catalyst sol alone was applied, and NiFeCrAl (average pore size: 1,200 μm) was applied as a porous metal support.

[0203] <Comparative Example 4>

[0204] A catalyst was prepared in the same manner as in Example 9 above, except that a perovskite catalyst sol was not applied, perovskite catalyst particles alone were applied, and NiFeCrAl (average pore size: 3,000 μm) was applied as a porous metal support.

[0205] <Comparative Example 5>

[0206] A catalyst was prepared in the same manner as in Example 8, except that perovskite catalyst particles alone were applied without applying a porous metal support and a perovskite catalyst sol.

[0207] <Comparative Example 6>

[0208] A catalyst was prepared in the same manner as Comparative Example 1, except that perovskite catalyst particles were not applied, a perovskite catalyst sol alone was applied, and NiCrAl (average pore size: 3,000 μm) was applied as a porous metal support.

[0209] The composition of the porous metal support, catalyst particles, and binder of the above examples and comparative examples is shown in Table 1 below.

[0210] [Table 1]

[0211]

[0212] <Experimental Example 1> Evaluation of Catalyst for Methane Reforming

[0213] An electron microscope image of the surface of a methane reforming catalyst according to Example 1 of the present application is shown in Fig. 1 below.

[0214] When preparing the methane reforming catalysts of the above examples and comparative examples, the content of the perovskite-based catalyst supported on the porous metal support after a single coating was measured and is shown in Table 2 below. In addition, in the methane reforming catalysts of the above examples and comparative examples, the presence or absence of protrusions on the surface of the catalyst particles coated on the porous metal support was checked and is shown in Table 2 below.

[0215] The above catalyst loading amount can be calculated using the following mathematical formula 1, and the presence or absence of protrusions can be confirmed by observing surface images through SEM.

[0216] [Mathematical Formula 1]

[0217] Catalyst loading amount (wt%) = (Total catalyst weight - Weight of porous metal support) / (Total catalyst weight) × 100

[0218] [Table 2]

[0219]

[0220] As shown in the results above, in Comparative Examples 1 to 3, the amount of catalyst supported per single coating was small, so the number of coatings had to be increased, which resulted in increased process costs, and in Comparative Example 4, no catalyst was attached at all. In addition, in Comparative Example 5, the amount supported on the porous metal support could not be measured because catalyst particles were applied alone, and in Comparative Example 6, the amount of active metal capable of performing the role of a catalyst could not be measured.

[0221] <Experimental Example 2> Evaluation of Methane Reforming Reaction

[0222] A fixed-bed reaction system was introduced to carry out the dry reforming reaction of methane. A quartz tube reactor (inner diameter = 1 / 2 inch, length = 50 cm) was used and the catalyst (approx. 2.5 g) of each example and comparative example was packed. First, a reduction process was carried out at 800°C for 2 hours under 10% H2 / N2 conditions, followed by a catalytic reaction for 100 hours.

[0223] Gas composition: CH4: CO2: N2 = 1 : 1.2 : 0.96

[0224] Flow rate: WHSV (Weight Hour Space Velocity) = 3,000 cc / g·hr ~ 100,000 cc / g·hr

[0225] Reaction temperature: 800℃

[0226] Reaction pressure: 1 bar

[0227] The reaction conversion rate after 100 hours of reaction was calculated by analyzing the composition of the generated gas using gas chromatography (GC), and is shown in Table 3 below.

[0228] Conversion Rate (Xi, %) = [(Fi in - Fi out ) / Fi in ] Х 100 (Fi = flow rate of i)

[0229] <GC 분석 조건>

[0230] 1) GC model: Agilent 6890

[0231] 2) Oven temp.: 40℃ / 7min-90℃ / 5min-180℃ / 6min

[0232] 3) Detector: TCD, 250℃

[0233] 4) Sample loop: 0.25 mL

[0234] 5) Valve box Temp.: 150℃

[0235] [Table 3]

[0236]

[0237] As shown in the above results, it can be confirmed that the catalyst for methane reforming according to one embodiment of the present application exhibits excellent methane conversion rate and CO2 conversion rate during the methane reforming reaction.

[0238] A catalyst for methane reforming according to one embodiment of the present application is prepared by mixing a catalyst sol of the same or similar series as the catalyst particles with an inorganic binder to form a slurry, and then coating this slurry onto a metal support with high thermal conductivity. This allows for an increase in the amount of catalyst supported at once and suppresses side reactions caused by the binder.

[0239] In addition, the catalyst for methane reforming according to one embodiment of the present application has the characteristic that reaction heat control is easy compared to conventional pellet-type or powder-type catalysts, as catalyst particles and a binder are supported on a porous metal support with high thermal conductivity.

Claims

Claim 1 A catalyst for methane reforming comprising: a porous metal support; perovskite-based catalyst particles supported on the porous metal support; and a perovskite-based binder supported on the porous metal support, wherein the perovskite-based catalyst particles and the perovskite-based binder each independently comprise a compound represented by the following chemical formula 1: [Chemical Formula 1]Sr 1-x A x Ti 1-y B y O 3-δ In the above chemical formula 1, A is Y or La, B is Ni, Co, Fe, Mn, Cr, Mo, Ru or Rh, x is a real number greater than or equal to 0 and less than 1, y is a real number greater than or equal to 0 and less than 0.5, δ is a real number greater than 0 and less than 1, and x + y > 0 is satisfied. Claim 2 The methane reforming catalyst of claim 1, wherein Chemical Formula 1 is represented by any one of the following Chemical Formulas 2 to 4: [Chemical Formula 2]SrTi 1-y B y O 3-δ [Chemical Formula 3]Sr 1-x Y x TiO 3-δ [Chemical Formula 4]Sr 1-x Y x Ti 1-y B y O 3-δ In the above chemical formulas 2 to 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 0.5, and δ is a real number greater than 0 and less than 1. Claim 3 A methane reforming catalyst according to claim 1, wherein the perovskite-based catalyst particles and the perovskite-based binder comprise compounds different from each other. Claim 4 A methane reforming catalyst according to claim 1, wherein the perovskite-based catalyst particles and the perovskite-based binder comprise the same compound. Claim 5 A methane reforming catalyst according to claim 1, wherein the porous metal support is composed of one or more materials selected from NiFeCrAl, NiCrAl, Al, stainless steel, and Inconel. Claim 6 A methane reforming catalyst according to claim 1, wherein, based on the total weight of the methane reforming catalyst, the total content of the perovskite-based catalyst particles and the perovskite-based binder is 3% to 40% by weight. Claim 7 A methane reforming catalyst according to claim 1, wherein at least a portion of the surface of the perovskite-based catalyst particles includes a protrusion shape. Claim 8 The methane reforming catalyst of claim 1, wherein the methane reforming catalyst is applied to a steam reforming process, a CO2 reforming process, a catalytic partial oxidation process, an autothermal reforming process, a tri-reforming process, or a mixed reforming process. Claim 9 A method for preparing a catalyst for methane reforming, comprising the steps of: mixing perovskite-based catalyst particles and a perovskite-based catalyst sol to prepare a slurry; impregnating a porous metal support into the slurry; and drying and calcining, wherein the perovskite-based catalyst particles and the perovskite-based catalyst sol each independently comprise a compound represented by the following Chemical Formula 1: [Chemical Formula 1]Sr 1-x A x Ti 1-y B y O 3-δ In the above chemical formula 1, A is Y or La, B is Ni, Co, Fe, Mn, Cr, Mo, Ru or Rh, x is a real number greater than or equal to 0 and less than 1, y is a real number greater than or equal to 0 and less than 0.5, δ is a real number greater than 0 and less than 1, and x + y > 0 is satisfied. Claim 10 A method for manufacturing a catalyst for methane reforming according to claim 9, wherein Chemical Formula 1 is represented by any one of the following Chemical Formulas 2 to 4: [Chemical Formula 2]SrTi 1-y B y O 3-δ [Chemical Formula 3]Sr 1-x Y x TiO 3-δ [Chemical Formula 4]Sr 1-x Y x Ti 1-y B y O 3-δ In the above chemical formulas 2 to 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 0.5, and δ is a real number greater than 0 and less than 1. Claim 11 A method for manufacturing a methane reforming catalyst according to claim 9, wherein the porous metal support is composed of one or more materials selected from NiFeCrAl, NiCrAl, Al, stainless steel, and Inconel.

Images