Composite metal oxide catalyst for methane dry reforming reaction, preparation method therefor, and hydrogen and carbon monoxide production system using same

Abstract

A composite metal oxide catalyst preparing method according to the present invention may comprise the steps of: preparing a mesoporous support including magnesium and aluminum; and providing a nickel source and a cobalt source to the mesoporous support and firing same, thereby preparing the composite metal oxide catalyst.

Description

Composite metal oxide catalyst for methane dry reforming reaction, method for preparing the same, and hydrogen and carbon monoxide production system using the same

[0001] The present invention relates to a composite metal oxide catalyst for methane dry reforming, a method for producing the same, and a hydrogen and carbon monoxide production system using the same, and more specifically, to a composite metal oxide catalyst comprising magnesium, aluminum, nickel, cobalt, and oxygen and having a mesoporous structure, a method for producing the same, and a hydrogen and carbon monoxide production system using the same.

[0002]

[0003] Methane dry reforming reaction is a reaction that uses methane and carbon dioxide, which are major greenhouse gases, to obtain hydrogen and carbon monoxide.

[0004] Recently, methane dry reforming has been attracting increased attention with the advent of the Fischer-Tropsch process. Accordingly, various catalysts for methane dry reforming are being developed.

[0005] For example, Korean Patent Publication No. 10-2619167 discloses a method for producing a catalyst for methane dry reforming, wherein nickel nanocrystals are dispersed inside a silica shell layer, the method comprising the steps of preparing a colloidal solution of a nickel hydroxide sheet, encapsulating the nickel hydroxide sheet with silica to form a silica shell layer having a secondary planar structure surrounding the nickel hydroxide sheet, and heat-treating the silica shell layer and the nickel hydroxide sheet.

[0006]

[0007] The technical problem to be solved by the present invention is to provide a method for producing a composite metal oxide catalyst having improved conversion rates of methane and carbon dioxide and improved production of hydrogen and carbon monoxide.

[0008] Another technical problem to be solved by the present invention is to provide a method for producing a composite metal oxide catalyst having a spinel crystal structure and improved crystallinity of the spinel crystal structure.

[0009] Another technical problem to be solved by the present invention is to provide a composite metal oxide catalyst that prevents the accumulation of carbon on the surface of a reduced composite metal oxide catalyst in a methane dry reforming reaction and reduces the temperature of a methane decomposition reaction and a carbon dioxide reduction reaction (Buddha reaction).

[0010] Another technical problem that the present invention seeks to solve is to provide a method for manufacturing a composite metal oxide catalyst with reduced manufacturing process costs.

[0011] Another technical problem that the present invention seeks to solve is to provide a method for producing a composite metal oxide catalyst with a shortened production time.

[0012] Another technical problem that the present invention seeks to solve is to provide a method for producing a composite metal oxide catalyst that is easy to mass-produce.

[0013] The technical problems to be solved by the present invention are not limited to those described above.

[0014]

[0015] To solve the above technical problem, the present invention provides a method for producing a composite metal oxide catalyst.

[0016] According to one embodiment, the method for preparing the composite metal oxide catalyst may include the steps of preparing a mesoporous support including magnesium and aluminum, and the steps of providing a nickel source and a cobalt source to the mesoporous support and calcining the mesoporous support to prepare the composite metal oxide catalyst.

[0017] In one embodiment, the mesoporous support may be manufactured by an evaporation-induced self-assembly method.

[0018] According to one embodiment, the method for producing the mesoporous support may include the steps of preparing an organic template, a magnesium source, and an aluminum source, dissolving the organic template in ethanol and providing nitric acid and stirring to produce a base source, providing the magnesium source immediately after providing the aluminum source while stirring the base source to produce a mesoporous support source, and calcining the mesoporous support source to produce the mesoporous support including magnesium and aluminum.

[0019] According to one embodiment, the magnesium of the magnesium source may be controlled to be greater than 5 mol% and less than 10 mol% relative to the aluminum of the aluminum source.

[0020] In one embodiment, the magnesium source may comprise magnesium nitrate hexahydrate, the aluminum source may comprise aluminum isopropoxide, and the organic template may comprise a Pluronic P123 copolymer.

[0021] According to one embodiment, in the step of preparing the composite metal oxide catalyst, the nickel source and the cobalt source may be mixed in ethanol and provided to the mesoporous support.

[0022] According to one embodiment, the amount of the cobalt source provided may be controlled so that the weight ratio of cobalt in the composite metal oxide catalyst is greater than 1 wt% and less than 3 wt%.

[0023] In one embodiment, the nickel source may include nickel nitrate hexahydrate, and the cobalt source may include cobalt nitrate hexahydrate.

[0024] In order to solve the above technical problem, the present invention provides a composite metal oxide catalyst manufactured by the above-described manufacturing method.

[0025] According to one embodiment, the composite metal oxide comprises a mesoporous support comprising magnesium and aluminum, and nickel aluminum oxide and cobalt aluminum oxide impregnated on the surface of the mesoporous support, the size of the pores being greater than 4.78 nm and less than or equal to 5.53 nm, and the volume of the pores being 0.36 cm 3 / g exceeds 0.40cm 3 / g or less, and the specific surface area is 269.48 m 2 / g exceeds 335.73m 2 / g and may include grain sizes greater than 5.79 nm and less than 7.18 nm.

[0026] According to one embodiment, the mesoporous support may include a regularly arranged tube shape, and the crystal structure of the mesoporous support may include a spinel crystal structure.

[0027] According to one embodiment, the composite metal oxide catalyst may include a weight ratio of cobalt of more than 1 wt% and less than 3 wt%.

[0028] In order to solve the above technical problem, the present invention provides a hydrogen and carbon monoxide production system using the above-described composite metal oxide catalyst.

[0029] According to one embodiment, in the hydrogen and carbon monoxide production system using a composite metal oxide catalyst containing magnesium, aluminum, nickel, cobalt, and oxygen and having a mesoporous structure, the hydrogen and carbon monoxide production system includes a reactor in which the composite metal oxide catalyst is disposed, a hydrogen supply unit for supplying hydrogen to the reactor, a methane supply unit for supplying methane to the reactor, and a carbon dioxide supply unit for supplying carbon dioxide after supplying the methane to the reactor, wherein the temperature of the reactor is controlled to a first temperature, hydrogen is supplied from the hydrogen supply unit, and the composite metal oxide catalyst disposed in the reactor is reduced, wherein the temperature of the reactor is controlled to a second temperature lower than the first temperature, methane is supplied from the methane supply unit, and the methane is decomposed into carbon and hydrogen to produce hydrogen, and carbon is adsorbed on the surface of the reduced composite metal oxide catalyst, wherein the temperature of the reactor is controlled to the second temperature, carbon dioxide is supplied from the carbon dioxide supply unit, and the reduced composite metal oxide is produced. This may include carbon adsorbed on the surface of the catalyst reacting with carbon dioxide to produce carbon monoxide.

[0030] According to one embodiment, the method may include controlling the second temperature to 700°C or lower by the composite metal oxide catalyst, increasing the production amount of hydrogen generated from the decomposition of methane by the composite metal oxide catalyst, and increasing the production amount of carbon monoxide generated from the reduction of carbon dioxide by the composite metal oxide catalyst.

[0031]

[0032] A method for producing a composite metal oxide catalyst according to the present invention may include a step of preparing a mesoporous support including magnesium and aluminum, and a step of providing a nickel source and a cobalt source to the mesoporous support and calcining the mesoporous support to produce the composite metal oxide catalyst.

[0033] The step of preparing the mesoporous support may include the steps of preparing an organic template, a magnesium source, and an aluminum source, dissolving the organic template (e.g., Pluronic P123 copolymer) in ethanol and providing nitric acid and stirring to prepare a base source, providing the aluminum source (e.g., aluminum isopropoxide) immediately after providing the magnesium source (e.g., magnesium nitrate hexahydrate) while stirring the base source to prepare a mesoporous support source, and calcining the mesoporous support source to prepare the mesoporous support including magnesium and aluminum.

[0034] In the step of manufacturing the mesoporous support source, the molar ratio of magnesium in the magnesium source provided to the base source can be controlled to be greater than 5 mol% and less than 10 mol% relative to the aluminum in the aluminum source. Accordingly, the mesoporous support can be provided with improved chemical stability, mechanical safety, and electronic conductivity, and with improved stability for catalytic activity in a methane dry reforming reaction.

[0035] In addition, in the step of preparing the mesoporous support source, the magnesium source may be provided immediately after the aluminum source is provided while stirring the base source. Accordingly, the aluminum source and the magnesium source may be completely dissolved in the base source. Accordingly, the mesoporous support (e.g., MgAl2O4) with improved crystallinity of the spinel crystal structure may be provided.

[0036] And, in the step of providing the nickel source (e.g., nickel nitrate hexahydrate) and the cobalt source (e.g., cobalt nitrate hexahydrate) to the mesoporous support and calcining them to prepare the composite metal oxide catalyst, the amount of the cobalt source provided can be controlled so that the weight ratio of cobalt in the composite metal oxide catalyst is more than 1 wt% and less than 3 wt%. Accordingly, in a methane dry reforming reaction, the composite metal oxide catalyst can be provided in which the conversion rates of methane and carbon dioxide are improved and the production amounts of hydrogen and carbon monoxide are improved.

[0037] The composite metal oxide catalyst manufactured by the above-described manufacturing method may include the mesoporous support (e.g., MgAl2O4) including magnesium and aluminum, and nickel aluminum oxide (e.g., NiAl2O4) and cobalt aluminum oxide (e.g., CoAl2O4) impregnated on the surface of the mesoporous support. In addition, the size of the pores of the composite metal oxide catalyst (200) is greater than 4.78 nm and less than or equal to 5.53 nm, and the volume of the pores is 0.36 cm 3 / g exceeds 0.40cm 3 / g or less, and the specific surface area is 269.48 m 2 / g exceeds 335.73m 2 / g or less, and the grain size may be greater than 5.79 nm and less than 7.18 nm. In addition, the weight ratio of cobalt in the composite metal oxide catalyst (200) may be greater than 1 wt% and less than 3 wt%.

[0038] Accordingly, in a methane dry reforming reaction including a methane decomposition reaction and a carbon dioxide reduction reaction (Buddha reaction), the temperature required for the methane decomposition reaction can be reduced by the composite metal oxide catalyst. Accordingly, the energy required for the methane dry reforming reaction can be reduced. In addition, the problem of carbon being adsorbed and accumulated on the surface of the composite metal oxide catalyst in the methane decomposition reaction can be prevented. Accordingly, the composite metal oxide catalyst can be provided which improves the conversion rate of methane and carbon dioxide in the methane dry reforming reaction.

[0039] Therefore, the above composite metal oxide catalyst can be used in a hydrogen and carbon monoxide production system.

[0040]

[0041] FIG. 1 is a flowchart illustrating a method for manufacturing a composite metal oxide catalyst according to an embodiment of the present invention.

[0042] FIG. 2 is a flowchart illustrating a method for manufacturing a mesoporous support according to an embodiment of the present invention.

[0043] FIG. 3 is a drawing for explaining a method for manufacturing a mesoporous support source according to an embodiment of the present invention.

[0044] FIG. 4 is a drawing for explaining a method for manufacturing a mesoporous support by drying and calcining a mesoporous support source according to an embodiment of the present invention.

[0045] FIG. 5 is a drawing for explaining a method for producing a composite metal oxide catalyst by providing a nickel source and a cobalt source to a mesoporous support and calcining the same.

[0046] Figure 6 is a diagram for explaining a methane dry reforming reaction of a hydrogen and carbon monoxide production system using a composite metal oxide catalyst.

[0047] FIG. 7 is a graph for comparing the pore volume and specific surface area of ​​a mesoporous support according to Experimental Example 1 of the present invention and a composite metal oxide catalyst according to Experimental Examples 1 to 6.

[0048] Figure 8 is a graph showing XRD analysis of a mesoporous support according to Experimental Example 1 of the present invention and a composite metal oxide catalyst according to Experimental Examples 1 to 6.

[0049] Figure 9 is a graph showing the analysis of the composite metal oxide catalyst according to Experimental Examples 1 to 6 of the present invention using H2-TPR (H2-Temperature Programmed Reduction).

[0050] Figure 10 is a TEM photograph of a mesoporous support according to Experimental Example 1 of the present invention.

[0051] Figure 11 is an EDS analysis image of a composite metal oxide catalyst according to Experimental Example 5 of the present invention.

[0052] Figure 12 is a graph for comparing the conversion rates of methane and carbon dioxide in a methane dry reforming reaction using a composite oxide catalyst according to Experimental Examples 1 to 6 of the present invention.

[0053] Figure 13 is a graph for explaining a methane dry reforming reaction using a composite oxide catalyst according to Experimental Example 5 of the present invention.

[0054] Figure 14 is a graph showing the conversion rates of methane and carbon dioxide according to the temperature of the methane decomposition reaction and the Buda reaction in the methane dry reforming reaction using the composite metal oxide catalyst according to Experimental Example 5 of the present invention.

[0055] FIG. 15 is a graph for comparing the conversion rates of methane and carbon dioxide in a methane dry reforming reaction using a composite metal oxide catalyst according to Experimental Example 1, Comparative Example 1, and Comparative Example 2 of the present invention.

[0056] FIG. 16 is a graph for comparing the conversion rates of methane and carbon dioxide in a methane dry reforming reaction using a composite metal oxide catalyst according to Comparative Examples 2, 3, and 4 of the present invention.

[0057] Figure 17 is a graph showing XRD analysis of mesoporous supports according to Comparative Examples 1, 3, 4, 5, 6, and 7 of the present invention.

[0058]

[0059] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. However, the technical concept of the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosed content is thorough and complete and to sufficiently convey the spirit of the present invention to those skilled in the art.

[0060] In this specification, when a component is referred to as being on another component, it means that it can be formed directly on the other component, or a third component may be interposed between them. In addition, in the drawings, the thicknesses of films and regions are exaggerated for the purpose of effectively explaining the technical contents.

[0061] Also, although terms such as first, second, and third have been used to describe various components in various embodiments of this specification, these components should not be limited by these terms. These terms are only used to distinguish one component from another. Thus, what is referred to as a first component in one embodiment may be referred to as a second component in another embodiment. Each embodiment described and illustrated herein also includes its complementary embodiments. Also, the term "and / or" has been used herein to mean including at least one of the components listed before and after.

[0062] In the specification, singular expressions include plural expressions unless the context clearly dictates otherwise. In addition, terms such as "comprise" or "have" are intended to specify the presence of a feature, number, step, component, or combination thereof described in the specification, and should not be construed as excluding the presence or addition of one or more other features, numbers, steps, components, or combinations thereof. In addition, the term "connection" is used in the present specification to mean both indirectly connecting multiple components and directly connecting them.

[0063] In addition, when describing the present invention below, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description will be omitted.

[0064]

[0065] FIG. 1 is a flowchart for explaining a method for producing a composite metal oxide catalyst according to an embodiment of the present invention, FIG. 2 is a flowchart for explaining a method for producing a mesoporous support according to an embodiment of the present invention, FIG. 3 is a drawing for explaining a method for producing a mesoporous support source according to an embodiment of the present invention, FIG. 4 is a drawing for explaining a method for producing a mesoporous support by drying and calcining a mesoporous support source according to an embodiment of the present invention, and FIG. 5 is a drawing for explaining a method for producing a composite metal oxide catalyst by providing a nickel source and a cobalt source to a mesoporous support and calcining it.

[0066] Referring to FIGS. 1 to 4, a mesoporous support (100) containing magnesium and aluminum is prepared (S110).

[0067] The step of preparing the mesoporous support (100) may include a step of preparing an organic template, a magnesium source, and an aluminum source (S112), a step of dissolving the organic template in ethanol, providing nitric acid, and stirring to prepare a base source (110) (S114), a step of providing the magnesium source immediately after providing the aluminum source while stirring the base source (110) to prepare a mesoporous support source (120) (S116), and a step of calcining the mesoporous support source (120) to prepare the mesoporous support (100) including magnesium and aluminum (S118). For example, the mesoporous support (100) may be prepared by an evaporation-induced self-assembly method.

[0068] In the step of preparing the organic template, the magnesium source, and the aluminum source, for example, the organic template may be a Pluronic P123 copolymer. For example, the magnesium source may be magnesium nitrate hexahydrate. For example, the aluminum source may be aluminum isopropoxide. Accordingly, the mesoporous support (100) produced may be, for example, MgAl2O4.

[0069] And, in the step of manufacturing the mesoporous support source (120), the molar ratio of magnesium in the magnesium source provided to the base source (110) can be controlled to be more than 5 mol% and less than 10 mol% relative to the aluminum in the aluminum source. Accordingly, the mesoporous support (100) has a spinel crystal structure, so that not only is chemical stability, mechanical stability, and electronic conductivity improved, but also the stability for catalytic activity in a methane dry reforming reaction including a methane decomposition reaction and a carbon dioxide reduction reaction (Buddha reaction) can be improved.

[0070] In contrast, when the molar ratio of magnesium in the magnesium source provided to the base source (110) is controlled to 5 mol% or less relative to the aluminum in the aluminum source, the mesoporous support (100) may not have a spinel crystal structure. Accordingly, the chemical stability, mechanical stability, and electronic conductivity of the mesoporous support (100) may be significantly reduced.

[0071] And, when the molar ratio of magnesium of the magnesium source provided to the base source (110) is controlled to be 10 mol% or more compared to aluminum of the aluminum source, the mesoporous support (100) has a spinel crystal structure, but the stability for catalytic activity in a methane dry reforming reaction may be reduced.

[0072] Therefore, in the method for manufacturing the mesoporous support (100) according to the present application embodiment, the molar ratio of magnesium in the magnesium source provided to the base source (110) can be controlled to be greater than 5 mol% and less than 10 mol% relative to the aluminum in the aluminum source. Accordingly, the mesoporous support (100) can be provided with improved chemical stability, mechanical safety, and electronic conductivity, and with improved stability for catalytic activity in a methane dry reforming reaction.

[0073] In addition, in the step of manufacturing the mesoporous support source (120), the magnesium source should be provided immediately after the aluminum source is provided while stirring the base source (110), so that the aluminum source and the magnesium source can be completely dissolved in the base source (110). Accordingly, the crystallinity of the spinel crystal structure of the mesoporous support (100) can be improved.

[0074] In contrast, if the magnesium source is provided first while stirring the base source (110) or if the magnesium source is provided after a period of time rather than immediately after providing the aluminum source while stirring the base source (110), the aluminum source and the magnesium source may not be completely dissolved in the base source (110). Accordingly, the crystallinity of the spinel crystal structure of the mesoporous support (100) may be reduced.

[0075] Therefore, in the method for manufacturing the mesoporous support (100) according to the embodiment of the present application, the magnesium source may be provided immediately after the aluminum source is provided while stirring the base source (110). Accordingly, the aluminum source and the magnesium source may be completely dissolved in the base source (110). Accordingly, the mesoporous support (100) with improved crystallinity of the spinel crystal structure may be provided.

[0076] Referring to FIGS. 1 and 5, a nickel source and a cobalt source are provided to the mesoporous support (100) and calcined to produce the composite metal oxide catalyst (200) (S120).

[0077] In the step of manufacturing the above composite metal oxide catalyst (200), the nickel source and the cobalt source may be mixed in ethanol and provided to the mesoporous support (100). For example, the nickel source may be nickel nitrate hexahydrate. For example, the cobalt source may be cobalt nitrate hexahydrate.

[0078] And, in the step of manufacturing the composite metal oxide catalyst (200), the amount of the cobalt source provided can be controlled so that the weight ratio of cobalt in the composite metal oxide catalyst (200) is greater than 1 wt% and less than 3 wt%. Accordingly, in the methane dry reforming reaction using the composite metal oxide catalyst (200), the conversion rate of methane and carbon dioxide can be improved, and the production amount of hydrogen and carbon monoxide can be improved.

[0079] In contrast, when the amount of the cobalt source provided is controlled so that the weight ratio of cobalt in the composite metal oxide catalyst (200) is 1 wt% or less or 3 wt% or more, in a methane dry reforming reaction using the composite metal oxide catalyst (200), the conversion rate of methane and carbon dioxide may decrease, and the production amount of hydrogen and carbon monoxide may decrease.

[0080] Therefore, in the method for manufacturing the composite metal oxide catalyst (200) according to the embodiment of the present application, the amount of the cobalt source provided can be controlled so that the weight ratio of cobalt in the composite metal oxide catalyst (200) is greater than 1 wt% and less than 3 wt%. Accordingly, in a methane dry reforming reaction, the composite metal oxide catalyst (200) can be provided in which the conversion rate of methane and carbon dioxide is improved and the production amount of hydrogen and carbon monoxide is improved.

[0081] In conclusion, the method for producing the composite metal oxide catalyst (200) according to the present application example may include a step of preparing the mesoporous support (100) including magnesium and aluminum, and a step of providing the nickel source and the cobalt source to the mesoporous support (100) and calcining it to produce the composite metal oxide catalyst (200).

[0082] The step of preparing the mesoporous support (100) may include a step of preparing the organic template, the magnesium source, and the aluminum source, a step of dissolving the organic template in ethanol, providing nitric acid, and stirring to prepare the base source (110), a step of providing the magnesium source immediately after providing the aluminum source while stirring the base source (110), to prepare the mesoporous support source (120), and a step of calcining the mesoporous support source (120) to prepare the mesoporous support (100) including magnesium and aluminum.

[0083] In the step of manufacturing the mesoporous support source (120), the molar ratio of magnesium in the magnesium source provided to the base source (110) can be controlled to be greater than 5 mol% and less than 10 mol% relative to the aluminum in the aluminum source. Accordingly, the mesoporous support (100) can be provided with improved chemical stability, mechanical safety, and electronic conductivity, and with improved stability for catalytic activity in a methane dry reforming reaction.

[0084] In addition, in the step of manufacturing the mesoporous support source (120), the magnesium source may be provided immediately after the aluminum source is provided while stirring the base source (110). Accordingly, the aluminum source and the magnesium source may be completely dissolved in the base source (110). Accordingly, the mesoporous support (100) with improved crystallinity of the spinel crystal structure may be provided.

[0085] And, in the step of providing the nickel source and the cobalt source to the mesoporous support (100) and calcining to manufacture the composite metal oxide catalyst (200), the amount of the cobalt source provided can be controlled so that the weight ratio of cobalt in the composite metal oxide catalyst (200) is greater than 1 wt% and less than 3 wt%. Accordingly, in a methane dry reforming reaction, the composite metal oxide catalyst (200) can be provided in which the conversion rate of methane and carbon dioxide is improved and the production amount of hydrogen and carbon monoxide is improved.

[0086] The composite metal oxide catalyst (200) manufactured by the above-described manufacturing method may include magnesium, aluminum, nickel, cobalt, and oxygen, and may have a mesoporous structure. Specifically, the composite metal oxide catalyst (200) may include the mesoporous support (100) including magnesium and aluminum, and nickel aluminum oxide and cobalt aluminum oxide impregnated on the surface of the mesoporous support (100). For example, the mesoporous support (100) may have a regularly arranged tube shape. For example, the mesoporous support (100) may have a spinel crystal structure. For example, the mesoporous support (100) may be MgAl2O4. For example, the nickel aluminum oxide may be NiAl2O4. For example, the cobalt aluminum oxide may be CoAl2O4. And, the pore size of the composite metal oxide catalyst (200) is greater than 4.78 nm and less than or equal to 5.53 nm, and the pore volume is 0.36 cm 3 / g exceeds 0.40cm 3 / g or less, and the specific surface area is 269.48 m 2 / g exceeds 335.73m 2 / g or less, and the grain size may be greater than 5.79 nm and less than 7.18 nm. In addition, the weight ratio of cobalt in the composite metal oxide catalyst (200) may be greater than 1 wt% and less than 3 wt%.

[0087] Accordingly, in a methane dry reforming reaction including a methane decomposition reaction and a carbon dioxide reduction reaction (Buddha reaction), the temperature required for the methane decomposition reaction can be reduced by the composite metal oxide catalyst (200). Accordingly, the energy required for the methane dry reforming reaction can be reduced. In addition, the problem of carbon being adsorbed and accumulated on the surface of the composite metal oxide catalyst (200) in the methane decomposition reaction can be prevented. Accordingly, the composite metal oxide catalyst (200) with an improved conversion rate of methane and carbon dioxide in a methane dry reforming reaction can be provided.

[0088]

[0089] Hereinafter, a hydrogen and carbon monoxide production system using the above-described composite metal oxide catalyst is described, and with reference to FIG. 6, a methane dry reforming reaction using the hydrogen and carbon monoxide production system is described.

[0090] Figure 6 is a diagram for explaining a methane dry reforming reaction of a hydrogen and carbon monoxide production system using a composite metal oxide catalyst.

[0091] Referring to FIGS. 1 to 5, the above-described composite metal oxide catalyst (200) is provided.

[0092] As described above, the composite metal oxide catalyst (200) may include magnesium, aluminum, nickel, cobalt, and oxygen, and may have a mesoporous structure. Specifically, the composite metal oxide catalyst (200) may include a mesoporous support (100) including magnesium and aluminum, and nickel aluminum oxide and cobalt aluminum oxide impregnated on the surface of the mesoporous support (100). For example, the mesoporous support (100) may have a regularly arranged tube shape. For example, the mesoporous support (100) may have a spinel crystal structure. For example, the mesoporous support (100) may be MgAl2O4. For example, the nickel aluminum oxide may be NiAl2O4. For example, the cobalt aluminum oxide may be CoAl2O4. And, the pore size of the composite metal oxide catalyst (200) is greater than 4.78 nm and less than or equal to 5.53 nm, and the pore volume is 0.36 cm 3 / g exceeds 0.40cm 3 / g or less, and the specific surface area is 269.48 m 2 / g exceeds 335.73m 2 / g or less, and the grain size may be greater than 5.79 nm and less than 7.18 nm. In addition, the weight ratio of cobalt in the composite metal oxide catalyst (200) may be greater than 1 wt% and less than 3 wt%.

[0093] The hydrogen and carbon monoxide production system may include a reactor in which the composite metal oxide catalyst (200) is provided, a hydrogen supply unit for supplying hydrogen to the reactor, an inert gas supply unit for supplying an inert gas to the reactor, a methane supply unit for supplying methane to the reactor, and a carbon dioxide supply unit for supplying carbon dioxide after supplying the methane to the reactor.

[0094] Before performing a methane dry reforming reaction of the hydrogen and carbon monoxide production system, the composite metal oxide catalyst (200) disposed in the reactor may be pretreated. That is, the composite metal oxide catalyst (200) may be reduced. Specifically, while the temperature of the reactor is controlled to a first temperature, hydrogen may be supplied from the hydrogen supply unit, and the composite metal oxide catalyst (200) disposed in the reactor may be reduced. For example, the first temperature may be 800°C. In addition, by supplying an inert gas to the reactor from the inert gas supply unit, unreacted hydrogen with the composite metal oxide catalyst (200) within the reactor may be removed. Accordingly, before performing a methane dry reforming reaction of the hydrogen and carbon monoxide production system, the reduced composite oxide catalyst (200) may be prepared.

[0095] Referring to FIG. 6, the methane dry reforming reaction of the hydrogen and carbon monoxide production system is performed.

[0096] The methane dry reforming reaction may include a methane decomposition reaction in which methane (CH4) is decomposed into carbon (C) and hydrogen (2H2) to produce hydrogen, as illustrated in FIG. 6, and a Buda reaction in which carbon (C) decomposed by the methane decomposition reaction reacts with carbon dioxide (CO2) to produce carbon monoxide.

[0097] The methane decomposition reaction of the hydrogen and carbon monoxide production system may be performed by supplying methane from the methane supply unit, decomposing methane into carbon and hydrogen to produce hydrogen while the temperature of the reactor is controlled to a second temperature lower than the first temperature, and adsorbing carbon on the surface of the reduced composite metal oxide catalyst (200). In the methane decomposition reaction of the hydrogen and carbon monoxide production system, methane is easily decomposed by the reduced composite metal oxide catalyst (200) of the reactor, thereby improving the conversion rate of methane and the production amount of hydrogen, and the problem of carbon accumulating on the surface of the reduced composite metal oxide catalyst (200) may be prevented. For example, the second temperature may be 700°C. In addition, by supplying an inert gas from the inert gas supply unit to the reactor, unreacted methane within the reactor may be removed.

[0098] Next, the Buda reaction of the hydrogen and carbon monoxide production system can be performed by supplying carbon dioxide from the carbon dioxide supply unit while the temperature of the reactor is maintained at the second temperature, reacting the carbon dioxide with the carbon adsorbed on the surface of the reduced composite metal oxide catalyst (200), and reducing the carbon dioxide to produce carbon monoxide. In the Buda reaction of the hydrogen and carbon monoxide production system, carbon dioxide can be easily reduced by the reduced composite metal oxide catalyst (200) of the reactor, thereby improving the conversion rate of carbon dioxide and the production amount of carbon monoxide.

[0099]

[0100] Hereinafter, specific experimental examples and characteristic evaluation results of composite metal oxide catalysts according to embodiments of the present invention are described.

[0101]

[0102] Mesoporous support according to Experimental Example 1

[0103] Pluronic P123 copolymer (5 g) was prepared as an organic template, magnesium nitrate hexahydrate (0.954 g) was prepared as a magnesium source, aluminum isopropoxide (10.2 g) was prepared as an aluminum source, and ethanol (100 mL) and nitric acid (concentration 98%, 8 mL) were prepared.

[0104] The organic template was dissolved in the ethanol at room temperature, nitric acid was added, and stirring (280 rpm, 1 hour) was performed to prepare a base source.

[0105] Then, immediately after adding the aluminum source while stirring the base source, the magnesium source was added and stirred (for 6 hours) to prepare a mesoporous support source.

[0106] Then, the mesoporous support source was dried in an oven (60°C, 2 days), and after confirming that a bright yellow solid material was formed in the mesoporous support source, the dried mesoporous source was first fired in an oven (400°C, 4 hours) and then second fired (800°C, 2 hours), thereby manufacturing a mesoporous support.

[0107]

[0108] Mesoporous support according to comparative example 1

[0109] A mesoporous support was prepared in the same manner as the mesoporous support according to Experimental Example 1, except that the amount of magnesium nitrate hexahydrate as a magnesium source was changed to 1.409 g.

[0110]

[0111] Mesoporous support according to comparative example 2

[0112] A mesoporous support was prepared in the same manner as the mesoporous support according to Experimental Example 1, except that no magnesium source was provided in the base source solution.

[0113]

[0114] Mesoporous support according to comparative example 3

[0115] A mesoporous support was prepared in the same manner as the mesoporous support according to Experimental Example 1, except that the amount of magnesium nitrate hexahydrate was changed to 1.409 g as the magnesium source, and that the aluminum source was provided to the base source and the magnesium source was provided 1 hour later.

[0116]

[0117] Mesoporous support according to comparative example 4

[0118] A mesoporous support was prepared in the same manner as the mesoporous support according to Experimental Example 1, except that the amount of magnesium nitrate hexahydrate was changed to 1.409 g as the magnesium source and the aluminum source was provided immediately after the magnesium source was provided to the base source.

[0119]

[0120] Mesoporous support according to comparative example 5

[0121] A mesoporous support was manufactured in the same manner as the mesoporous support according to Experimental Example 1, except that the amounts of the magnesium source and the aluminum source were controlled so that the molar ratio of magnesium in the magnesium source and aluminum in the aluminum source was 5:95.

[0122]

[0123] Mesoporous support according to comparative example 6

[0124] A mesoporous support was manufactured in the same manner as the mesoporous support according to Experimental Example 1, except that the amounts of the magnesium source and the aluminum source were controlled so that the molar ratio of magnesium in the magnesium source and aluminum in the aluminum source was 2:98.

[0125]

[0126] Mesoporous support according to comparative example 7

[0127] A mesoporous support was manufactured in the same manner as the mesoporous support according to Experimental Example 1, except that the amounts of the magnesium source and the aluminum source were controlled so that the molar ratio of magnesium in the magnesium source and aluminum in the aluminum source was 1:99.

[0128]

[0129] Composite metal oxide catalyst according to Experimental Example 1

[0130] A mesoporous support was prepared according to Experimental Example 1, nickel nitrate hexahydrate (0.607 g) was prepared as a nickel source, and ethanol (0.6 mL) was prepared.

[0131] The nickel source was provided to the ethanol at room temperature and stirred (30 minutes) to prepare a nickel source solution.

[0132] Then, the nickel source solution was supplied to the mesoporous support using a syringe (40 mL / min), and dried in an oven (80°C, 12 hours) to remove the ethanol.

[0133] Then, the temperature of the oven was increased to 450°C at a heating rate of 1°C / min, followed by a first firing (450°C, 30 minutes), and then increased from 450°C to 800°C at a heating rate of 1°C / min, followed by a second firing (800°C, 2 hours), thereby manufacturing a composite metal oxide catalyst.

[0134]

[0135] Composite metal oxide catalyst according to Experimental Example 2

[0136] A mesoporous support was prepared according to Experimental Example 1, nickel nitrate hexahydrate (0.607 g) was prepared as a nickel source, cobalt nitrate hexahydrate (0.015 g) was prepared as a cobalt source, and ethanol (0.6 mL) was prepared.

[0137] The nickel source and the cobalt source were provided in the ethanol at room temperature and stirred (30 minutes) to prepare a mixed metal source solution.

[0138] Then, the mixed metal source solution was supplied to the mesoporous support using a syringe (40 mL / min), and dried in an oven (80°C, 12 hours) to remove the ethanol.

[0139] Then, the temperature of the oven was increased to 450°C at a heating rate of 1°C / min, followed by a first firing (450°C, 30 minutes), and then increased from 450°C to 800°C at a heating rate of 1°C / min, followed by a second firing (800°C, 2 hours), thereby manufacturing a composite metal oxide catalyst.

[0140]

[0141] Composite metal oxide catalyst according to Experimental Example 3

[0142] A composite metal oxide catalyst was prepared in the same manner as the composite metal oxide catalyst according to Experimental Example 2, except that the amount of cobalt nitrate hexahydrate as a cobalt source material was changed to 0.025 g.

[0143]

[0144] Composite metal oxide catalyst according to Experimental Example 4

[0145] A composite metal oxide catalyst was prepared in the same manner as the composite metal oxide catalyst according to Experimental Example 2, except that the amount of cobalt nitrate hexahydrate as a cobalt source material was changed to 0.051 g.

[0146]

[0147] Composite metal oxide catalyst according to Experimental Example 5

[0148] A composite metal oxide catalyst was prepared in the same manner as the composite metal oxide catalyst according to Experimental Example 2, except that the amount of cobalt nitrate hexahydrate as a cobalt source material was changed to 0.102 g.

[0149]

[0150] Composite metal oxide catalyst according to Experimental Example 6

[0151] A composite metal oxide catalyst was prepared in the same manner as the composite metal oxide catalyst according to Experimental Example 2, except that the amount of cobalt nitrate hexahydrate as a cobalt source material was changed to 0.153 g.

[0152]

[0153] Composite metal oxide catalyst according to comparative example 1

[0154] A composite metal oxide catalyst was prepared in the same manner as the composite metal oxide catalyst according to Experimental Example 1, except that the amount of nickel nitrate hexahydrate as a nickel source was changed to 0.759 g.

[0155]

[0156] Composite metal oxide catalyst according to comparative example 2

[0157] A composite metal oxide catalyst was prepared in the same manner as the composite metal oxide catalyst according to Experimental Example 1, except that the amount of nickel nitrate hexahydrate as a nickel source was changed to 1.012 g.

[0158]

[0159] Composite metal oxide catalyst according to Comparative Example 3

[0160] A composite metal oxide catalyst was prepared in the same manner as the composite metal oxide catalyst according to Experimental Example 1, except that a mesoporous support was prepared according to Comparative Example 1 and the amount of nickel nitrate hexahydrate as a nickel source was changed to 1.012 g.

[0161]

[0162] Composite metal oxide catalyst according to Comparative Example 4

[0163] A composite metal oxide catalyst was prepared in the same manner as the composite metal oxide catalyst according to Experimental Example 1, except that a mesoporous support was prepared according to Comparative Example 2 and the amount of nickel nitrate hexahydrate as a nickel source was changed to 1.012 g.

[0164] Classification Ni content Co content Experimental example 1 Mesoporous support MgAl2O4 (Mg:Al = 7:93, mole ratio)--Comparative example 1 MgAl2O4 (Mg:Al = 10:90, mole ratio)--Comparative example 2 Al2O4--Comparative example 3 MgAl2O4 (Mg:Al = 10:90, mole ratio)--Comparative example 4 MgAl2O4 (Mg:Al = 10:90, mole ratio)--Comparative example 5 MgAl2O4 (Mg:Al = 5:95, mole ratio)--Comparative example 6 MgAl2O4 (Mg:Al = 2:98, mole ratio)--Comparative example 7 MgAl2O4 (Mg:Al = 1:99 mole ratio)--Experimental example 1 Composite metal oxide CatalystNi / MgAl2O4(Mg:Al = 7: 93, mole ratio)12wt%-Experimental Example 2Ni-Co / MgAl2O4(Mg:Al = 7: 93, mole ratio)12wt%0.3wt%Experimental Example 3Ni-Co / MgAl2O4(Mg:Al = 7: 93, mole ratio)12w%0.5wt%Experimental Example 4Ni-Co / MgAl2O4(Mg:Al = 7: 93, mole ratio)12wt%1.0wt%Experimental Example 5Ni-Co / MgAl2O4(Mg:Al = 7: 93, mole ratio)12wt%2.0wt%Experimental Example 6NiCoMgAl(Mg:Al = 7: 93, mole ratio)12wt%3.0wt%Comparative Example 1Composite metal oxide Catalyst Ni / MgAl2O4 (Mg:Al = 7: 93, mole ratio) 15 wt% - Comparative Example 2 Ni / MgAl2O4 (Mg:Al = 7: 93, mole ratio) 20 wt% - Comparative Example 3 Ni / MgAl2O4 (Mg:Al = 10:90, mole ratio) 20 wt% - Comparative Example 4 Ni / Al2O4 20 wt% -

[0165]

[0166] FIG. 7 is a graph for comparing the pore volume and specific surface area of ​​a mesoporous support according to Experimental Example 1 of the present invention and a composite metal oxide catalyst according to Experimental Examples 1 to 6, and FIG. 8 is a graph for analyzing a mesoporous support according to Experimental Example 1 of the present invention and a composite metal oxide catalyst according to Experimental Examples 1 to 6 using XRD.

[0167] Referring to Fig. 7 a), the pore volume of the mesoporous support (blue legend) according to Experimental Example 1 (EX-1) and the composite metal oxide catalysts according to Experimental Examples 1 (EX-1) to 6 (EX-6) were measured. Referring to Fig. 7 b), the specific surface area of ​​the mesoporous support (blue legend) according to Experimental Example 1 (EX-1) and the composite metal oxide catalysts according to Experimental Examples 1 (EX-1) to 6 (EX-6) were measured through nitrogen adsorption. Referring to Fig. 8, XRD analysis was performed on the mesoporous support (blue legend) according to Experimental Example 1 (EX-1) and the composite metal oxide catalysts according to Experimental Examples 1 (EX-1) to 6 (EX-6) using Cu-Kα radiation (λ=0.15418 nm, 4° / min, 10° to 80°). The results are summarized in Table 2 below.

[0168] As can be seen in Figures 7a), b), and , the pore volume of the mesoporous support according to Experimental Example 1 is 0.62 cm 3 / g can be used to find the largest one.

[0169] And, the pore volume of the composite metal oxide catalyst according to Experimental Examples 1 to 6 is 0.36 cm 3 / g to 0.40cm 3 / g can be seen to be at a similar level.

[0170] In addition, it can be seen that the composite metal oxide catalysts according to Experimental Examples 1 to 6 have a smaller specific surface area than the mesoporous support according to Experimental Example 1.

[0171] This factor is interpreted to be due to the fact that, in the method for producing the composite metal oxide catalyst according to Experimental Examples 1 to 6, a nickel source and a cobalt source are provided to the mesoporous support.

[0172] As can be seen in FIG. 8 and , in the mesoporous support according to Experimental Example 1, peaks corresponding to the MgAl2O4 crystal structure were observed at 23.99°, 31.76°, and 65.05°.

[0173] And, in the composite metal oxide catalysts according to Experimental Examples 1 to 6, it can be seen that the intensity of the peak observed in the composite metal oxide catalysts according to Experimental Examples 1 to 6 is generally increased compared to the intensity of the peak observed in the mesoporous support according to Experimental Example 1, due to the peak corresponding to the NiAl2O4 crystal structure occurring at substantially the same position as the peak corresponding to the MgAl2O4 crystal structure.

[0174] In addition, it can be seen that the peaks corresponding to the NiAl2O4 crystal structure observed in the composite metal oxide catalysts according to Experimental Examples 1 to 6 are stronger and shifted to the left than the peaks corresponding to the MgAl2O4 crystal structure at 19.01°, 31.32°, 36.94°, 44.99°, 59.82°, 65.70°, and 77.21°.

[0175] And, when comparing the peaks corresponding to the CoAl2O4 crystal structure observed in the composite metal oxide catalysts according to Experimental Examples 1 to 6, it can be seen that as the cobalt content increases, the intensity of the peak corresponding to the CoAl2O4 crystal structure increases.

[0176] Surface area of ​​the spherical secretion (m) 2 / g)Pore size (nm)Pore volume (cm) 3 / g)2θGrain size (nm)Experimental example 1Mesoporous supportMgAl2O4398.396.230.6223.993.56Experimental example 1Composite metal oxideNi / MgAl2O4311.355.100.4036.945.08Experimental example 2Composite metal oxideNi-Co / MgAl2O4308.985.070.3936.955.13Experimental example 3Composite metal oxideNi-Co / MgAl2O4318.425.070.4036.955.23Experimental example 4Composite metal oxideNi-Co / MgAl2O4335.734.780.4036.875.79Experimental example 5Composite metal Experimental Example 6: Composite Metal Oxide Ni-Co / MgAl2O4 2 8 7 3 4 5 5 3 0 4 0 3 6 8 1 6 1 3

[0177]

[0178] Figure 9 is a graph showing the analysis of the composite metal oxide catalyst according to Experimental Examples 1 to 6 of the present invention using H2-TPR (H2-Temperature Programmed Reduction).

[0179] Referring to FIG. 9, after the composite metal oxide catalysts according to Experimental Examples 1 (EX-1) to 6 (EX-6) were pretreated (Ar gas atmosphere, 350°C, 1 hour), the temperature provided to the composite metal oxide catalysts according to Experimental Examples 1 (EX-1) to 6 (EX-6) was increased from 50°C to 1,000°C (10°C / min) in a H2 / Ar (10% / 90%) gas atmosphere, and the H2-TPR analysis was performed by maintaining the temperature at 1,000°C for 10 minutes.

[0180] As can be seen in Fig. 9, in the H2-TPR profiles for the composite metal oxide catalysts according to Experimental Examples 1 to 6, it can be seen that the peak corresponding to H2 consumption is observed as a single peak at about 820°C.

[0181] In addition, the fact that no peak was observed below about 820°C in the H2-TPR profiles for the composite metal oxide catalysts according to Experimental Examples 1 to 6 is interpreted as being due to the stability of nickel aluminum oxide in the composite metal oxide catalysts according to Experimental Examples 1 to 6.

[0182] And, when comparing the H2-TPR profile for the composite metal oxide catalyst according to Experimental Example 1 and the H2-TPR profile for the composite metal oxide catalyst according to Experimental Examples 2 to 6, unlike the composite metal oxide catalyst according to Experimental Example 1, cobalt aluminum oxide is present in the composite metal oxide catalyst according to Experimental Examples 2 to 6, so that a nickel cobalt alloy is formed, and it can be seen that the peak corresponding to H2 consumption observed in the composite metal oxide catalyst according to Experimental Examples 2 to 6 is shifted to the right compared to the peak corresponding to H2 consumption observed in the composite metal oxide catalyst according to Experimental Example 1.

[0183]

[0184] Figure 10 is a TEM photograph of a mesoporous support according to Experimental Example 1 of the present invention.

[0185] Referring to a) and b) of Fig. 10, the mesoporous support according to Experimental Example 1 was photographed using TEM.

[0186] As can be seen from a) and b) of Fig. 10, the mesoporous support according to Experimental Example 1 is in the form of regularly arranged tubes.

[0187]

[0188] Figure 11 is an EDS analysis image of a composite metal oxide catalyst according to Experimental Example 5 of the present invention.

[0189] Referring to a) to c) of Fig. 11, EDS analysis was performed on the surface of the composite metal oxide catalyst according to Experimental Example 5.

[0190] As can be seen from a) to c) of Fig. 11, nickel, cobalt, magnesium, aluminum, and oxygen are uniformly dispersed on the surface of the composite metal oxide catalyst according to Experimental Example 5.

[0191]

[0192] Figure 12 is a graph for comparing the conversion rates of methane and carbon dioxide in a methane dry reforming reaction using a composite oxide catalyst according to Experimental Examples 1 to 6 of the present invention.

[0193] Referring to FIG. 12, 0.1 g of the composite oxide catalysts according to Experimental Examples 1 to 6 (EX-1) were provided in a reactor (atmospheric pressure, quartz wool arranged on both sides), and while the temperature of the reactor was controlled to 800°C, H2 / N2 (10% / 90%) gas was supplied to the reactor to reduce the composite oxide catalysts according to Experimental Examples 1 to 6. Then, high-purity N2 gas was supplied to remove the H2 gas remaining in the reactor. Subsequently, while the temperature of the reactor was controlled to 700°C, CH4 / N2 gas was supplied to the reactor at a rate of 30 ccm for 30 minutes to decompose CH4 (methane decomposition reaction). Then, high-purity N2 gas was supplied to remove the CH4 gas remaining in the reactor. Next, while maintaining the temperature of the reactor at 700°C, CO2 / N2 gas was supplied to the reactor for 15 minutes to reduce CO2 (Buddha reaction). The above-described methane decomposition reaction → high-purity N2 gas supply → Buddha reaction was repeated three times as a unit cycle, and the components and amounts of gases generated from the methane decomposition reaction and Buddha reaction were measured using gas chromatography. The results are summarized in Table 3 below.

[0194] As can be seen in Fig. 12 and , in the methane dry reforming reaction using the composite metal oxide catalyst according to Experimental Examples 1 to 6, it can be seen that the conversion rate of methane is higher than that of carbon dioxide.

[0195] And, as the weight ratio of cobalt in the composite metal oxide catalyst increases, the conversion rate of carbon dioxide increases (the composite metal oxide according to Experimental Examples 2 to 5), but when the weight ratio of cobalt in the composite metal oxide catalyst is 3 wt% or more (the composite metal oxide catalyst according to Experimental 6), it can be seen that the conversion rate of carbon dioxide decreases.

[0196] In addition, among the composite metal oxide catalysts according to Experimental Examples 1 to 6, in the methane dry reforming reaction using the composite metal oxide catalyst according to Experimental Example 2, the largest amount of hydrogen (88.20 mmole / g) was produced. cat ) and carbon monoxide (55.59 mmole / g cat ) can be seen to have been produced.

[0197] Therefore, in the method for manufacturing a composite metal oxide catalyst according to the present application, it can be seen that the method of controlling the weight ratio of cobalt in the composite metal oxide catalyst to be more than 1 wt% (lower limit) and less than 3 wt% (upper limit) is a method for improving the conversion rate of methane and carbon dioxide in a methane dry reforming reaction and improving the production amount of hydrogen and carbon monoxide.

[0198] Classification Co Weight Ratio (wt%) CH4 Conversion Rate (%) H2 Production (mmol / g) cat )CO2 conversion rate (%)CO2 production (mmol / g) cat)Experimental Example 10.075.1082.4140.8780.9Experimental Example 20.375.2090.0137.8675.2Experimental Example 30.574.3080.6440.2079.6Experimental Example 41.077.8380.5541.2981.8Experimental Example 52.081.3088.2047.1793.5Experimental Example 63.070.2074.5339.1780.8

[0199]

[0200] Figure 13 is a graph for explaining a methane dry reforming reaction using a composite oxide catalyst according to Experimental Example 5 of the present invention.

[0201] Referring to a) of Fig. 13, the conversion rate of methane was measured while performing the methane decomposition reaction → high-purity N2 gas supply → Buda reaction 20 times in total as a unit cycle in the same manner as the methane dry reforming reaction described above in Fig. 12 using the composite oxide catalyst according to Experimental Example 5, and the conversion rate of carbon dioxide was measured while performing the unit cycle 20 times in total, and the production amount and purity of H2, CO2, and CO gases were measured while performing the unit cycle 20 times in total, and the production amount of H2 and CO gases was measured while performing the unit cycle 20 times in total, and the ratio of CO gas to the produced H2 was calculated. The results are summarized in and below.

[0202] As can be seen from a) to d of Fig. 13), , and , in the methane dry reforming reaction using the composite metal oxide catalyst according to Experimental Example 5, after performing the unit cycle a total of 20 times, the total production amount of hydrogen and carbon monoxide is 23.97 mmole / g. catAnd, the conversion rates of methane and carbon dioxide are 45.4% and 24.95%, respectively, the purity of the produced hydrogen is maintained at 80% or more, and the purity of the produced carbon monoxide (14.06%) is found to have increased compared to the initial cycle (3.86%).

[0203] Classification CH4 conversion rate (%) H2 production (mmol / g) cat )CO production in CH4 decomposition reaction (mmol / g) cat )CO2 conversion rate (%)CO2 production (mmol / g) cat )Cycle 189.334.241.3952.8734.90Cycle 279.529.491.9446.2730.60Cycle 366.622.622.3937.8025.00Cycle 454.017.801.4933.2822.00Cycle 557.418.512.2632.6921.70Cycle 652.915.752.4729.1719.30Cycle 754.017.752.3330.7020.30Cycle 853.017.812.4430.5420.20Cycle 949.115.461.9928.2018.70Cycle 1050.316.272.4428.1618.70Cycle 1144.813.571.9026.2217.40Cycle 1242.713.001.9726.0617.30Cycle 1350.115.782.6927.0418.00Cycle 1447.414.532.3126.8717.80Cycle 1547.814.762.4626.9217.90Cycle 1644.912.991.4526.7717.80Cycle 1749.015.122.4025.8217.10Cycle 1841.411.671.5624.1516.00Cycle 1947.914.352.5324.9516.60Cycle 2045.413.902.3724.9516.60

[0204] Classification H2 Purity (%) CO Purity (%) CO2 Purity (%) Cycle 195.06 3.86 1.08 Cycle 292.47 6.08 1.44 Cycle 387.10 9.20 3.70 Cycle 490.36 7.56 2.08 Cycle 584.9 110.37 4.72 Cycle 680.56 12.63 6.80 Cycle 786.37 11.34 2.29 Cycle 885.58 11.73 2.69 Cycle 986.03 11.07 2.89 Cycle 1084.78 12.71 2.50 Cycle 1185.24 11.93 2.83 Cycle 1284.4212.792.79Cycle 1383.0514.162.79Cycle 1483.7513.312.94Cycle 1583.2013.872.93Cycle 1685.129.505.37Cycle 1782.6713.124.21Cycle 1883.9011.214.89Cycle 1979.9014.096.01Cycle 2082.4414.063.50

[0205]

[0206] Figure 14 is a graph showing the conversion rates of methane and carbon dioxide according to the temperature of the methane decomposition reaction and the Buda reaction in the methane dry reforming reaction using the composite metal oxide catalyst according to Experimental Example 5 of the present invention.

[0207] Referring to a) and b) of FIG. 14, in the methane dry reforming reaction using the composite metal oxide catalyst according to Experimental Example 5 described above in FIG. 12, the temperature of the methane decomposition reaction was controlled to 600°C, and the temperature of the Buda reaction was controlled to 700°C, 750°C, 800°C, and 900°C, respectively, to measure the conversion rate of methane (a) of FIG. 14)) and the conversion rate of carbon dioxide (b) of FIG. 14)) over time.

[0208] As can be seen from a) and b) of Fig. 14, in the methane dry reforming reaction using the composite metal oxide catalyst according to Experimental Example 5, it can be seen that the conversion rate of carbon dioxide is the highest when the temperature of the Buda reaction is controlled to 700°C.

[0209]

[0210] FIG. 15 is a graph for comparing the conversion rates of methane and carbon dioxide in a methane dry reforming reaction using a composite metal oxide catalyst according to Experimental Example 1, Comparative Example 1, and Comparative Example 2 of the present invention.

[0211] Referring to a) and b) of FIG. 15, the methane dry reforming reaction was performed using a composite metal oxide catalyst according to Experimental Example 1 (EX-1), Comparative Example 1 (REF-1), and Comparative Example 2 (REF-2) in the same manner as the methane dry reforming method described above in FIG. 12, and the conversion rates of methane and carbon dioxide were measured.

[0212] As can be seen from a) and b) of FIG. 15, the catalytic activity of the composite metal oxide catalyst according to Experimental Example 1 is the highest in the methane decomposition reaction of the methane dry reforming reaction, and in the Buda reaction, the catalytic activity of the composite metal oxide catalyst according to Experimental Example 1 and Comparative Example 2 is lower than that of the composite metal oxide catalyst according to Comparative Example 1.

[0213] Therefore, it can be seen that the method of controlling the weight ratio of nickel in the composite metal catalyst according to the present application example to 12 wt% or less is a method of optimizing catalytic activity in a methane dry reforming reaction.

[0214]

[0215] FIG. 16 is a graph for comparing the conversion rates of methane and carbon dioxide in a methane dry reforming reaction using a composite metal oxide catalyst according to Comparative Examples 2, 3, and 4 of the present invention.

[0216] Referring to a) and b) of FIG. 16, the methane dry reforming reaction was performed using a composite metal oxide catalyst according to Comparative Example 2 (REF-2), Comparative Example 3 (REF-3), and Comparative Example 4 (REF-4) in the same manner as the methane dry reforming method described above in FIG. 12, and the conversion rates of methane and carbon dioxide were measured.

[0217] As can be seen in a) and b) of Fig. 16, the catalytic activity is most stable when the composite metal oxide catalyst according to Comparative Example 2 is used in the methane dry reforming reaction. This factor is interpreted to be due to the content of magnesium in the mesoporous support of the composite metal oxide catalyst.

[0218] Therefore, in the method for manufacturing a mesoporous support according to an embodiment of the present application, it can be seen that the method of controlling the molar ratio of magnesium in the magnesium source (magnesium nitrate hexahydrate) provided in the base source (organic template + ethanol + nitric acid) to less than 10 mol% relative to the aluminum in the aluminum source is a method for improving the stability of the catalytic activity of a composite metal oxide catalyst in a methane dry reforming reaction.

[0219]

[0220] Figure 17 is a graph showing XRD analysis of mesoporous supports according to Comparative Examples 1, 3, 4, 5, 6, and 7 of the present invention.

[0221] Referring to a) and b) of FIG. 17, the mesoporous supports according to Comparative Example 1 (REF-1), Comparative Example 3 (REF-3), Comparative Example 4 (REF-4), Comparative Example 5 (REF-5), Comparative Example 6 (REF-6), and Comparative Example 7 (REF-7) were analyzed by XRD.

[0222] As can be seen in a) and b) of Fig. 17, it can be seen that the peak corresponding to the spinel crystal structure is most clearly observed in the mesoporous support according to Comparative Example 1.

[0223] This factor is interpreted as being due to the fact that, in the method for producing the mesoporous support according to Comparative Example 1, the method of providing the magnesium source (magnesium nitrate hexahydrate) immediately after providing the aluminum source (aluminum isopropoxide) while stirring the base source (organic template + ethanol + nitric acid) is more effective than the method of providing the aluminum source while stirring the base source and then providing the magnesium source 1 hour later (the method for producing the mesoporous support according to Comparative Example 3), or the method of providing the aluminum source immediately after providing the magnesium source while stirring the base source (the method for producing the mesoporous support according to Comparative Example 3).

[0224] Therefore, in the method for manufacturing a mesoporous support according to an embodiment of the present application, it can be seen that the method of providing a magnesium source immediately after providing an aluminum source while stirring the base source is a method for manufacturing a mesoporous support with improved crystallinity of a spinel crystal structure.

[0225] And, in the method for manufacturing a mesoporous support according to comparative examples, when the molar ratio of magnesium in the magnesium source is controlled to 5 mol% or less relative to aluminum in the aluminum source (the mesoporous support according to comparative examples 5, 6, and 7), it can be seen that a peak corresponding to a spinel crystal structure is substantially not observed in the manufactured mesoporous support.

[0226] Therefore, in the method for manufacturing a mesoporous support according to the present application embodiment, it can be seen that the method for controlling the molar ratio of magnesium in the magnesium source provided to the base source to exceed 5 mol% (lower limit) relative to aluminum in the aluminum source is a method for manufacturing a mesoporous support having a spinel crystal structure.

[0227] In summary, considering the experimental results described above in FIG. 16, it can be seen that in the method for manufacturing a mesoporous support according to the embodiment of the present application, the method of controlling the molar ratio of magnesium in the magnesium source provided in the base source to be more than 5 mol% (lower limit) and less than 10 mol% (upper limit) relative to aluminum in the aluminum source is a method for improving the chemical stability, mechanical stability, and electronic conductivity of the mesoporous support by making the mesoporous support have a spinel crystal structure, as well as improving the stability for catalytic activity in a methane dry reforming reaction.

[0228]

[0229] While the present invention has been described in detail using preferred embodiments, the scope of the present invention is not limited to the specific embodiments described above, and should be interpreted in accordance with the appended claims. Furthermore, those skilled in the art will appreciate that numerous modifications and variations are possible without departing from the scope of the present invention.

Claims

1. A step of preparing a mesoporous support containing magnesium and aluminum; and A method for producing a composite metal oxide catalyst, comprising the step of providing a nickel source and a cobalt source to the mesoporous support and calcining the mesoporous support to produce a composite metal oxide catalyst.

2. In paragraph 1, A method for producing a composite metal oxide catalyst, comprising producing the mesoporous support by an evaporation-induced self-assembly method.

3. In paragraph 2, The method for manufacturing the above mesoporous support is as follows: Step of preparing an organic template, a magnesium source, and an aluminum source; A step of preparing a base source by dissolving the above organic template in ethanol, providing nitric acid, and stirring; A step of preparing a mesoporous support source by providing the magnesium source immediately after providing the aluminum source while stirring the base source; and A method for producing a composite metal oxide catalyst, comprising the step of producing a mesoporous support comprising magnesium and aluminum by calcining the mesoporous support source.

4. In paragraph 3, A method for producing a composite metal oxide catalyst, wherein the magnesium of the magnesium source is controlled to be greater than 5 mol% and less than 10 mol% relative to the aluminum of the aluminum source.

5. In paragraph 4, The above magnesium source includes magnesium nitrate hexahydrate, The above aluminum source comprises aluminum isopropoxide, The above organic template is a method for producing a composite metal oxide catalyst comprising a Pluronic P123 copolymer.

6. In paragraph 1, A method for producing a composite metal oxide catalyst, comprising, in the step of producing the composite metal oxide catalyst, mixing the nickel source and the cobalt source in ethanol and providing them to the mesoporous support.

7. In paragraph 6, A method for producing a composite metal oxide catalyst, comprising controlling the amount of the cobalt source provided so that the weight ratio of cobalt in the composite metal oxide catalyst is greater than 1 wt% and less than 3 wt%.

8. In paragraph 6, The above nickel source comprises nickel nitrate hexahydrate, The above cobalt source is a method for producing a composite metal oxide catalyst including cobalt nitrate hexahydrate.

9. Mesoporous support comprising magnesium and aluminum; and Comprising nickel aluminum oxide and cobalt aluminum oxide impregnated on the surface of the mesoporous support, The pore size includes those exceeding 4.78 nm and less than or equal to 5.53 nm, The pore volume is 0.36 cm 3 / g exceeds 0.40cm 3 / Including those below g, The specific surface area is 269.48 m 2 / g exceeds 335.73m 2 / Including those less than g, A composite metal oxide catalyst comprising a grain size greater than 5.79 nm and less than 7.18 nm.

10. In paragraph 9, The mesoporous support comprises a regularly arranged tube shape, A composite metal oxide catalyst comprising a spinel crystal structure of the mesoporous support.

11. In paragraph 10, A composite metal oxide catalyst comprising a weight ratio of cobalt in the composite metal oxide catalyst of more than 1 wt% and less than 3 wt%.

12. In a hydrogen and carbon monoxide production system using a composite metal oxide catalyst containing magnesium, aluminum, nickel, cobalt, and oxygen and having a mesoporous structure, The production system of hydrogen and carbon monoxide A reactor in which the above composite metal oxide catalyst is placed; A hydrogen supply unit for supplying hydrogen to the above reactor; A methane supply unit for supplying methane to the above reactor; and Including a carbon dioxide supply unit that supplies carbon dioxide after supplying the methane to the above reactor, In a state where the temperature of the reactor is controlled to a first temperature, hydrogen is supplied from the hydrogen supply unit, and the composite metal oxide catalyst disposed in the reactor is reduced, In a state where the temperature of the reactor is controlled to a second temperature lower than the first temperature, methane is supplied from the methane supply unit, the methane is decomposed into carbon and hydrogen to produce hydrogen, and carbon is adsorbed on the surface of the reduced composite metal oxide catalyst. A hydrogen and carbon monoxide production system comprising a process in which carbon dioxide is supplied from the carbon dioxide supply unit while the temperature of the reactor is controlled to the second temperature, and carbon monoxide is produced by reacting carbon adsorbed on the surface of the reduced composite metal oxide catalyst with the carbon dioxide.

13. In paragraph 12, By the above composite metal oxide catalyst, the second temperature is controlled to 700°C or less, By the above composite metal oxide catalyst, the production amount of hydrogen generated from the decomposition of methane is increased, A hydrogen and carbon monoxide production system comprising an increase in the production amount of carbon monoxide generated by reduction of carbon dioxide by the composite metal oxide catalyst.

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