Carbon dioxide conversion catalyst for producing petroleum substitute organic material, and manufacturing method therefor

Abstract

The present invention relates to: a catalyst in which a rare earth metal is introduced into an iron-based catalyst so as to improve the degree of adsorption of CO2 and CO, thereby enabling effective direct conversion of CO2; and a manufacturing method therefor. The carbon dioxide conversion catalyst of the present invention exhibits, even under reaction conditions of H2 / CO2=1.6 or H2 / CO+CO2=1.28 and 20 bar, a CO2 conversion rate of 30% or higher and an naphtha yield of 30% or higher.

Description

Catalyst for converting carbon dioxide for the production of petroleum substitute organic compounds and method for producing the same

[0001] The present invention relates to a catalyst for carbon dioxide conversion for the production of petroleum substitute organic compounds and a method for producing the same, and more specifically, to a catalyst capable of effectively directly converting CO2 by introducing a rare earth metal into an iron-based catalyst and a method for producing the same.

[0002]

[0003] Since the Industrial Revolution, human energy consumption has steadily increased, and the world currently relies on fossil fuels like oil, coal, gas, and wood for over 80% of its energy. These fossil fuels inevitably emit CO2 when converted to energy during combustion. This CO2, which remains in the atmosphere, blocks energy reflected from the Earth's surface, contributing to the greenhouse effect and raising Earth's temperature.

[0004] As various greenhouse gas reduction plans are announced in accordance with mandatory greenhouse gas reduction, there is a growing interest in developing new technologies to reduce CO2 emissions, the main culprit of the greenhouse effect, or to convert emitted CO2 into other useful substances.

[0005] Many studies have been conducted to solve the CO2 problem, and one of them is to convert CO2 into petroleum substitute chemicals, such as base oil (C2~C4) and liquid transportation fuel (C5~C) through CO2 hydrogenation reaction. 12 ) has been studied. A large amount of CO2 can be effectively removed through the CO2 hydrogenation reaction, and in particular, the flue gas (HMP purge gas) discharged from the oil refining process contains an excessive amount of CO2 and some CO and CH4, so the CO2 generated through the utilization of the flue gas can be effectively reduced.

[0006] With growing interest in CO2 hydrogenation, numerous research results have been published in recent years. However, given the current high price of H2, converting CO2 into a petroleum substitute through CO2 hydrogenation is not cost-effective. Therefore, the development of a catalyst capable of effectively converting CO2 even at low hydrogen fractions is necessary.

[0007]

[0008] The present invention is intended to solve the problems of the prior art, and provides a catalyst with improved CO2 conversion rate and a method for manufacturing the same by introducing a rare earth metal into a generally well-known iron (Fe)-based catalyst.

[0009]

[0010] The catalyst for carbon dioxide conversion of the present invention is a compound represented by the following chemical formula 1, and can convert carbon dioxide into a hydrocarbon.

[0011] [Chemical Formula 1]

[0012] Fe a Cu b K c Al d (M) e

[0013] The 2θ value of the XRD of the above catalyst includes a peak of 35.89 to 35.93,

[0014] The above M includes at least one selected from rare earth metals including Ce, La, and Pr,

[0015] The composition ratios of a, b, c, d, and e above total 1.

[0016] The above hydrocarbons have carbon numbers of C2~C4 and C5~C 12 , and the catalyst is C5~C 12 / CH4yield ratio can be 10 to 15.

[0017] The above catalyst may have an XRD FWHM (full width at half maximum) value of 0.5 to 0.7, a crystallite size (particle size) of 10 to 20 nm, and a (M)O2 / Fe2O3 peak intensity ratio of 1.70 to 1.85.

[0018] The above catalyst is Fe by XPS 2+ / Fe 3+ The ratio can be between 1.0 and 1.4.

[0019] The above catalyst has a pore volume of 0.17 to 0.21 in BET analysis, and S BET 80 to 200 m 2 / g may be.

[0020] The above catalyst can be prepared through mixing and diffusion reactions of each constituent metal salt by mechanical shearing under solvent-free conditions.

[0021] The above metal salt comprises at least one compound selected from the group of organic compounds including nitrate, ammonium nitrate, carbonate, bicarbonate, hydroxide, oxide, oxyhydrate, acetate, and sulfate, and can be mixed in an equivalent ratio according to the composition ratio of the above chemical formula 1.

[0022] A method for producing a catalyst for carbon dioxide conversion represented by the following chemical formula 1 may include a step of producing a catalyst precursor through mixing and diffusion reaction of each constituent metal salt and base by mechanical shear force; and a step of producing a catalyst for carbon dioxide conversion by calcining the catalyst precursor at a high temperature.

[0023] [Chemical Formula 1]

[0024] Fe a Cu b K c Al d (M) e

[0025] The above M includes at least one selected from rare earth metals including Ce, La, and Pr,

[0026] The composition ratios of a, b, c, d, and e above total 1.

[0027] The above metal salt includes at least one compound selected from the group of organic compounds including nitrate, ammonium nitrate, carbonate, bicarbonate, hydroxide, oxide, oxyhydrate, acetate, and sulfate, and can be mixed in an equivalent ratio according to the composition ratio of the above chemical formula 1.

[0028] The above Base includes one or more bases selected from a group containing ammonium ions, the Base is NH4HCO3, and when 3a+2b+c+3d+3e in the above Chemical Formula 1 is f, the NH4HCO3 can be mixed in an equivalent ratio of f±0.05.

[0029] The above firing temperature is 300 to 1000 ℃, and the above firing time can be 30 minutes to 20 hours.

[0030]

[0031] The carbon dioxide conversion catalyst of the present invention improves the adsorption degree of CO2 and CO by introducing rare earth metals into an iron-based catalyst, thereby enabling effective direct conversion of CO2. In particular, it shows an efficiency of CO2 conversion rate of 30% or more and naphtha yield of 30% or more even under reaction conditions of H2 / CO2=1.6 or H2 / CO+CO2=1.28 and 20 bar. Through this, it is possible to produce base oil (C2~C4) and naphtha (C5~C) as petroleum substitute chemicals. 12 ) can be used to develop a catalyst process system capable of producing value-added chemicals.

[0032]

[0033] Figure 1 shows SEM and EDS mapping images of a catalyst prepared according to a catalyst synthesis method.

[0034] Figure 2 shows the XRD results of the catalyst according to the catalyst synthesis method.

[0035] Figure 3 shows the XPS results of the catalyst according to the catalyst synthesis method.

[0036] Figure 4 shows the carbon distribution results of the liquid product according to the synthesis method of the catalyst.

[0037] Figure 5 shows the XRD pattern of the catalyst according to the base type.

[0038] Figure 6 shows the results of CO2-TPD and CO-TPD analysis of catalysts according to base type.

[0039] Figure 7 shows the properties of the catalyst according to the amount of base added.

[0040] Figure 8 shows the XRD results of the catalyst according to the Fe content.

[0041] Figure 9 shows the results of CO2-TPD and H2-TPR analysis of the catalyst according to the Fe content.

[0042] Figure 10 shows the results of carbon distribution of liquid products according to Fe content.

[0043] Figure 11 shows TEM images of catalysts according to CeO2 content.

[0044] Figure 12 shows the XRD results of the catalyst according to the CeO2 content.

[0045] Figure 13 shows the results of H2-TPR, CO2-TPD, and CO-TPD analysis of the catalyst according to the CeO2 content.

[0046] Figure 14 shows the results of H2-TPR, CO2-TPD, and CO-TPD analyses of catalysts according to the type of rare earth metal.

[0047] Figure 15 shows the results of CO2-TPD and H2-TPR analysis of catalysts according to the type of heterometal.

[0048] Figure 16 shows the results of a long-term stability evaluation of a catalyst manufactured by the SSR method.

[0049] Figure 17 shows the results of carbon distribution of the liquid product during the long-term stability evaluation of the catalyst manufactured by the SSR method.

[0050] Figure 18 shows the results of carbon distribution of the liquid product during the long-term stability evaluation of the catalyst manufactured by the CP method.

[0051]

[0052] The embodiments described herein may be modified in various different forms, and the technology according to one embodiment is not limited to the embodiments described below. In addition, the embodiments of one embodiment are provided to more completely explain the present disclosure to a person with average knowledge in the relevant technical field. In this case, unless there is a different definition for the technical and scientific terms used, they have the meaning commonly understood by a person with ordinary skill in the technical field to which this invention belongs, and in the following description and the attached drawings, descriptions of well-known functions and configurations that may unnecessarily obscure the gist of the present invention are omitted.

[0053] Additionally, the singular forms used in this specification and the appended claims are intended to include the plural forms as well, unless the context clearly dictates otherwise.

[0054] Additionally, in this specification and the appended claims, the terms first, second, etc. are not used in a limiting sense but are used for the purpose of distinguishing one component from another.

[0055] Additionally, in this specification and the appended claims, when a part such as a film (layer), region or component is said to be located “on,” “above,” “upper,” “below,” “lower,” or “lower” another part, this includes not only cases where one part is in contact with another part, but also cases where another part exists between the two parts.

[0056] In addition, the terms "about," "substantially," and the like used in this specification and the appended claims are used in a meaning that is at or close to the numerical value when manufacturing and material tolerances inherent in the meanings stated are presented, and are used to prevent unscrupulous infringers from unfairly utilizing the disclosure in which exact or absolute values ​​are stated to aid in the understanding of this specification and the appended claims.

[0057] Additionally, the numerical ranges used herein include lower and upper limits and all values ​​within that range, increments logically derived from the shape and width of the defined range, all doubly defined values, and all possible combinations of upper and lower limits of numerical ranges defined in different shapes.

[0058] Furthermore, terms such as “include” or “have” in this specification and the appended claims mean that a feature or component described in the specification is present, and unless specifically limited, do not preclude the possibility that one or more other features or components may be added.

[0059]

[0060] Hereinafter, the catalyst for converting carbon dioxide for producing an organic substitute for petroleum according to the present invention and the method for producing the same will be described in detail with reference to the attached drawings.

[0061]

[0062] Hydrogenation is a metal-catalyzed reaction in which hydrogen molecules are added to a compound containing an unsaturated functional group, such as a double or triple bond. This reaction requires an unsaturated compound, hydrogen, and a catalyst. The reaction proceeds at various temperatures and pressures, depending on the activity of the catalyst and the type of reactant (unsaturated compound).

[0063]

[0064] The hydrogenation reaction of CO2 is as follows.

[0065] (1) reverse water gas shift reaction

[0066] CO2+ H2→ CO + H2O

[0067] (2) Carbon chain extension reaction

[0068] nCO + (2n+1)H2→ C n H 2n+2 + nH2O (n > 1)

[0069]

[0070] [Table 1] below shows the uses of the products obtained through the hydrogenation reaction of CO2 according to their carbon number range.

[0071]

[0072] Carbon number range classification application C1-C4 gaseous fuel, plastic synthetic raw material C5-C 12 Gasoline car fuel C 12 -C 16 Kerosene jet fuel, diesel oil C 16 -C 18 Diesel fuel, pyrolysis raw material C 18 -C 20 LubricantsLubricants, pyrolysis raw materialsC 20 -C 40 Paraffin Wax Wax C 40 Excess asphalt, asphalt, tar

[0073]

[0074] A crucial element in the CO2 hydrogenation reaction is the catalyst. Without a metal catalyst, hydrogen gas itself barely reacts with organic compounds. Cobalt- and iron-based catalysts are commonly used. Iron-based catalysts are relatively inexpensive, offer a wide range of reactor operating conditions, and produce a high proportion of higher-grade products, such as branched hydrocarbons and lower olefins, making them widely used.

[0075] However, in the case of the FeCuKAl catalyst, which is a well-known iron-based catalyst, there are disadvantages such as relatively low CO2 conversion and narrow CH4 selectivity.

[0076] In the hydrogenation reaction of CO2, the CO2 conversion rate and product yield can be improved by additionally supplying H2 or increasing the pressure to 30 bar or more.

[0077]

[0078] [Table 2] shows a comparison of reaction activity evaluations according to reaction conditions. Selectivity indicates the selectivity according to CO2 conversion.

[0079]

[0080] Reaction conditions X CO2 (%)Selectivity (%)P bar H2 / CO2COCH4C 2~4 C 5+ 201.627.210.84.130.165.8203.033.716.28.527.763.8303.039.817.810.925.863.3

[0081]

[0082] Thermodynamically, the required H2 / CO2=3 for CO2 hydrogenation reaction, and the reaction pressure is also 30~40 bar. The hydrogenation reaction activity of CO2 at this time is the reported value of CO2 conversion rate 40%, C 5+ The maximum ideal yield is 20%.

[0083] However, considering the process cost, this is inefficient. Therefore, catalyst development is needed to achieve the target yield without additional hydrogen and pressure supply. Therefore, the present invention aims to address the shortcomings of existing catalysts by applying rare earth metals as cocatalysts to iron-based catalysts, facilitating CO2 adsorption and desorption.

[0084]

[0085] Rare earth metals (REMs) are a group of 15 elements, ranging from lanthnum (atomic number 57) to lutetium (atomic number 71). These elements are chemically very stable, remain stable even in dry air, and conduct heat well. Furthermore, even in small quantities, they can maximize device performance, making them widely used in information technology (IT) electronics such as liquid crystal displays (LCDs), light-emitting diodes (LEDs), and smartphones, as well as military supplies such as missile control systems and fighter jets. Furthermore, they are also used as key elements in various fields, including phosphors, catalysts, abrasives, and alloying elements.

[0086] In particular, cerium (Ce), the most abundant rare earth metal, is a highly electropositive and chemically reactive metal that readily oxidizes to cerium(IV) oxide (CeO2) in air. The surface of cerium oxide is highly hydrophobic, a characteristic of rare earth metals, making it highly adsorbable to organic compounds. This property makes it useful as a variety of catalysts. In particular, CeO2 forms oxygen vacancies at the interface, which not only enhances its oxygen storage capacity but also significantly increases the rate of redox reactions.

[0087]

[0088] Accordingly, the present invention developed a catalyst in which the CO2 conversion rate is effectively improved by introducing the characteristics of CeO2 into the FeCuKAl catalyst, which is an iron-based catalyst.

[0089]

[0090] The catalyst for carbon dioxide conversion of the present invention is a compound represented by the following [chemical formula 1], which converts carbon dioxide into a hydrocarbon.

[0091]

[0092] [Chemical Formula 1]

[0093] Fe a Cu b K c Al d (M) e

[0094] The above M includes at least one selected from rare earth metals including Ce, La, and Pr,

[0095] The composition ratios of a, b, c, d, and e above total 1.

[0096]

[0097] The above catalyst is manufactured through a mixing and diffusion reaction of each constituent metal salt under solvent-free conditions through mechanical shear force. This is called the solid-state reaction (SSR) or solid-state reaction method. The solid-state reaction is a reaction in which substances mixed in a pure solid state are converted into new compounds under conditions such as temperature or pressure.

[0098] Conventionally, catalysts were manufactured by co-precipitation (CP) or impregnation (IMP), but in the present invention, the catalyst is manufactured by solid-state reaction (SSR), and the manufacturing method is simple compared to co-precipitation or impregnation, and a catalyst having uniform particles can be manufactured.

[0099] Each of the above metal salts comprises at least one compound selected from the group of organic compounds including nitrate, ammonium nitrate, carbonate, bicarbonate, hydroxide, oxide, oxyhydrate, acetate, and sulfate, and may preferably be a nitrate compound. In addition, the metal salts are used by mixing them in an equivalent ratio according to the composition ratio of the above chemical formula 1, and may be used as hydrates or anhydrides, but are not limited thereto.

[0100] In the present invention, as an example, each metal salt is described using a nitrate salt. According to an example, when a catalyst is synthesized by a solid-state method using a nitrate compound as each metal salt, water and a salt are generated through the following [Chemical Formula 2]. When NH4HCO3 is added as a base, it is important to adjust the amount of each metal salt and the amount of base so that the molar ratio of NH4NO3 and CO2 becomes 1.

[0101]

[0102] [Chemical Formula 2]

[0103] Acid + Base → salt↓ +H2O

[0104] ①aFe(NO3)3·9H2O + 3aNH4HCO3→aFeOOH + 3aNH4NO3+ 10aH2O + 3aCO2

[0105] ②bCu(NO3)2·3H2O + 2bNH4HCO3→bCuO + 2bNH4NO3+ 4bH2O + 2bCO2

[0106] ③cKNO3+cNH4HCO3→cKOH +cNH4NO3+cCO2

[0107] ④dAl(NO3)3·9H2O + 3dNH4HCO3→dAlOOH + 3dNH4NO3+ 10dH2O + 3dCO2

[0108] ⑤eCe(NO3)3·6H2O + 3eNH4HCO3→eCeOOH + 3eNH4NO3+ 7eH2O + 3eCO2

[0109] -----------------------------------------------------------------------

[0110] ⑥aFe(NO3)3·9H2O +bCu(NO3)2·3H2O +cKNO3+dAl(NO3)3·9H2O +eCe(NO3)3·6H2O + (3a+2b+c+3d+3e)NH4HCO3→ Fe a Cu b Al d Ce e Ox +cKOH + (3a+2b+c+3d+3e)NH4NO3+ (10a+4b+10d+7e)H2O + (3a+2b+c+3d+3e)CO2

[0111]

[0112] In the above chemical formula 2, 3a+2b+c+3d+3e is f.

[0113] The above a, b, c, d and e are the valences of the constituent metals, preferably independently 0.01 to 0.5, and the total may be 1.

[0114] The above NH4HCO3 is preferably used in an equivalent ratio of f±0.05, and preferably may be 1.5 to 3.0. As a non-limiting example, when a is 0.37, b is 0.04, c is 0.09, d is 0.47, and e is 0.03, f may be 2.73 to 2.83.

[0115] The catalyst manufactured by the above solid-state method is carbon dioxide having carbon numbers of C2~C4 and C5~C 12 Hydrocarbons, preferably having carbon numbers C5~C 12 It is converted into hydrocarbons, C5~C 12 / CH4yield ratio is 10 to 15.

[0116] The above catalyst has an XRD FWHM (full width at half maximum) value of 0.5 to 0.7, a crystallite size (particle size) of 10 to 20 nm, and a (M)O2 / Fe2O3 peak intensity ratio of 1.70 to 1.85.

[0117] In addition, the catalyst was Fe by XPS 2+ / Fe 3+ The ratio is 1.0 to 1.4, the pore volume of BET analysis is 0.17 to 0.21, and S BET 80 to 200 m 2 / g, 95 to 100 m 2 / g is.

[0118]

[0119] The method for producing a carbon dioxide conversion catalyst represented by the following chemical formula 1 of the present invention comprises the steps of producing a catalyst precursor through mixing and diffusion reaction of each constituent metal salt and base by mechanical shear force; and the step of producing a carbon dioxide conversion catalyst by calcining the catalyst precursor at high temperature.

[0120]

[0121] [Chemical Formula 1]

[0122] Fe a Cu b K c Al d (M) e

[0123] The above M includes at least one selected from rare earth metals including Ce, La, and Pr,

[0124] The composition ratios of a, b, c, d, and e above total 1.

[0125]

[0126] The above metal salt comprises at least one compound selected from the group of organic compounds including nitrate, ammonium nitrate, carbonate, bicarbonate, hydroxide, oxide, oxyhydrate, acetate, and sulfate, and is mixed in an equivalent ratio according to the composition ratio of the above chemical formula 1.

[0127] The above Base comprises one or more bases selected from the group containing ammonium ions, preferably NH4HCO3. In the above Chemical Formula 1, if 3a+2b+c+3d+3e is f, NH4HCO3 is mixed in an equivalent ratio of f±0.05.

[0128] The above firing conditions are not particularly limited and may be, for example, 300 to 1000°C, but are preferably 350 to 550°C, and more preferably 390 to 410°C.

[0129] The above firing time is not particularly limited and may be, for example, 30 minutes to 20 hours, but is preferably 2 hours to 10 hours, and more preferably 4 hours to 6 hours.

[0130] While mixing the above-described respective metal salts and base, the phase of the catalyst precursor changes from solid-liquid-solid to solid, and ultimately a gel-type catalyst precursor is obtained.

[0131]

[0132] Hereinafter, specific examples and experimental examples will be described. However, the examples and experimental examples described below are only illustrative, and the technology described in this specification is not limited thereto.

[0133]

[0134] <Example> Solid State Reaction (SSR)

[0135] 15.1 g of Fe(NO3)3·9H2O, 18.0 g of Al(NO3)3·9H2O, 0.98 g of Cu(NO3)2·3H2O, 0.93 g of KNO3, 1.5 g of Ce(NO3)3·6H2O, and 22.4 g of NH4NO3 were placed in a mortar and mixed at room temperature for 20 minutes, and then calcined at 400°C for 5 hours to obtain Fe 0.37 Cu 0.04 K 0.09 Ce 0.034 Al 0.47 A catalyst (SSR) was synthesized.

[0136]

[0137] <Comparative Example 1> Co-Precipitation (CP)

[0138] Fe(NO3)3·9H2O (15.1 g), Al(NO3)3·9H2O (18.0 g), Cu(NO3)2·3H2O (0.98 g), and Ce(NO3)3·6H2O (1.5 g) were completely dissolved in distilled water at room temperature, and then 22.1 g of K2CO3 was added while stirring at 60°C to prepare a FeCuCeAl solution. The pH of the FeCuCeAl solution was adjusted to pH 7 with K2CO3 solution, stirred at 80°C for 3 hours, and cooled to room temperature. The FeCuCeAl mixture precipitated from the FeCuCeAl solution was filtered and washed with distilled water to remove residual K and impurities, dried at 110°C overnight, and calcined at 400°C for 5 hours to synthesize a FeCuCeAl catalyst. Afterwards, the FeCuCeAl catalyst was impregnated with 12 wt% K (K / Fe = 0.12) using a KNO3 solution and calcined at 550°C for 5 hours to form Fe 0.37 Cu 0.04 K 0.09 Ce 0.034 Al 0.47 A catalyst (CP) was synthesized.

[0139]

[0140] <Comparative Example 2> Impregnation (IMP)

[0141] 3 g of CeAl was added to an aqueous solution of 15.1 g of Fe(NO3)3·9H2O, 0.98 g of Cu(NO3)2·3H2O, and 0.93 g of KNO3 dissolved in 10 mL of distilled water, stirred overnight at room temperature, dried overnight at 110°C, and calcined at 400°C for 5 hours to obtain Fe 0.37 Cu 0.04 K 0.09 / Ce 0.034 Al 0.47 A catalyst (IMP) was synthesized.

[0142]

[0143] <Reaction driving conditions>

[0144] These are the operating conditions for the CO2 hydrogenation reaction using the carbon dioxide conversion catalyst of the present invention. A down-flow stainless steel fixed-bed reactor with an inner diameter of ID 1 / 2" or 3 / 8" and a length of 40.7 mm was lined with glass wool, and 1.5 g of glass beads and 0.6 g of a carbon dioxide conversion catalyst in powder form, sieved through a 300 micrometer sieve, were inserted into the reactor. At atmospheric pressure, H2 / CO=2 was supplied, and the reaction was treated at 350°C for 5 h at a heating rate of 5°C / min, then pressurized to a maximum of 20 bar with N2 at room temperature and then feed was supplied. Under the above feed conditions, the reaction was performed at 300°C, 20 bar, and a space velocity of GHSV-1 6250 mL / gcat·h, and the reactants and products were analyzed online using a gas chromatograph.

[0145]

[0146] <Experimental Example 1> Comparison of catalyst synthesis methods

[0147] Figure 1 shows SEM and EDS mapping images of catalysts according to the catalyst synthesis method. (a) is a FeCuK20CeAl (SSR) catalyst manufactured by the SSR method, (b) is a FeCuK20CeAl (CP) catalyst manufactured by the CP method, and (c) is a FeCuK / 20CeAl (IMP) catalyst manufactured by the IMP method. It was confirmed that the catalyst manufactured by the SSR method had high metal dispersion and small particle size.

[0148]

[0149] Figure 2 and [Table 3] show the XRD results of the catalyst according to the catalyst synthesis method. Looking at Figure 2, a peak corresponding to CeO2 was confirmed at 33.3° and a peak corresponding to Fe2O3 was confirmed at 35.8°.

[0150]

[0151] Catalyst synthesis methodCatalyst name2θFWHMCrystallite size (nm)CeO2 / Fe2O3Peak intensity ratioSSRFeCuK20CeAl35.910.67121.74CPFeCuK20CeAl35.820.3281.08IMPFeCuK / 20CeAl35.760.15561.41

[0152]

[0153] [Table 3] The 2θ of the catalyst manufactured by the SSR method was measured to be 35.91, the FWHM (full width at half maximum) was 0.67, the crystallite size was 12 nm, and the CeO2 / Fe2O3 peak intensity ratio was 1.74. The 2θ of the catalyst manufactured by the CP method was measured to be 35.82, the FWHM was 0.3, the crystallite size was 28 nm, and the CeO2 / Fe2O3 peak intensity ratio was 1.08. In addition, the 2θ of the catalyst manufactured by the IMP method was measured to be 35.76, the FWHM was 0.15, the crystallite size was 56 nm, and the CeO2 / Fe2O3 peak intensity ratio was 1.41.

[0154]

[0155] Figure 3 shows the XPS results of the catalyst according to the synthesis method of the catalyst. Regardless of the synthesis method of the catalyst, all of them are Fe. 2+ Wow Fe 3+ It is a mixed form. Depending on the catalyst synthesis method, Fe 2+ / Fe 3+ The ratio is formed differently, and this is judged to be due to the influence of the dispersion state of each metal.

[0156] In addition, Fe according to the synthesis method of the catalyst of Fig. 3 2+ / Fe 3+ Looking at the ratio, the catalyst manufactured by the SSR method was measured at 1.2, the catalyst manufactured by the IMP method at 0.6, and the catalyst manufactured by the CP method at 0.4. In the case of the catalyst manufactured by the SSR method, the highest Fe was measured compared to the catalysts manufactured by other manufacturing methods. 2+ / Fe 3+ had a ratio of , and showed greater peak intensity.

[0157]

[0158] [Table 4] shows the evaluation of reaction activity according to the catalyst synthesis method. Yield represents the yield according to the conversion of CO+CO2.

[0159]

[0160] Catalyst Synthesis Method Catalyst Name Catalyst X CO+CO2 (%)X CO2 (%)Yield (%)C 5~12 / CH4yield ratioCH4C 2~4 C 5~12 C 13+ SSRFeCuK20CeAlFe 0.37 Cu 0.04 K 0.09 Ce 0.034 Al 0.47 36.825.91.510.618.06.012.0CPFeCuK20CeAlFe 0.37 Cu 0.04 K 0.09 Ce 0.034 Al0.47 27.817.64.26.611.25.82.7IMPFeCuK / 20CeAlFe 0.37 Cu 0.04 K 0.09 / Ce 0.034 Al 0.47 23.613.86.86.28.94.21.3

[0161]

[0162] As shown in [Table 4], the CO2 conversion rate of the catalyst manufactured by the SSR method was measured to be 25.9%, that of the catalyst manufactured by the CP method was measured to be 17.6%, and that of the catalyst manufactured by the IMP method was measured to be 13.8%. In addition, the C of the catalyst manufactured by the SSR method 5~12 The / CH4 yield ratio was measured to be 12.0, 2.7 for the catalyst manufactured by the CP method, and 1.3 for the catalyst manufactured by the IMP method. The difference in catalytic activity is judged to be due to the influence of the metal dispersion and particle state, and the CO2 conversion rate of the catalyst manufactured by the SSR method was 25.9%, C 5~12 / CH4 yield ratio is 12.0, the best C 5~12 The yield was 18.0%.

[0163]

[0164] Figure 4 shows the results of carbon distribution of liquid products according to the synthesis method of the catalyst. In the case of the catalyst manufactured by the CP method, C 13+ The distribution was higher for the catalyst manufactured by the SSR method. This is believed to be due to the increased occurrence of hydrogenation and thus increased CC coupling. This also suggests that the yield of CH4 was higher for the catalyst manufactured by the CP method.

[0165]

[0166] <Experimental Example 2> Effects according to base type

[0167] In the SSR method, the pH conditions for precipitation of each constituent metal salt are different, and are affected by the strength of the added base. The precipitation conditions for Fe, Cu, and Al are around pH 7-8, while CeO2 precipitates at a relatively high pH of 9-12.

[0168] By adding two bases with different basicity, we confirmed the difference in the properties of the catalyst as well as the reaction activity.

[0169]

[0170] The base strength of each base is different as follows.

[0171] - NH4HCO3: weak base (pH 7.5~8)

[0172] - (NH4)2CO3: base (pH 9~10)

[0173]

[0174] While the previously used NH4HCO3 ionizes into one ammonium when dissolved in water, (NH4)2CO3 has a relatively stronger basicity because two ammonium atoms exist.

[0175]

[0176] [Table 5] shows the BET analysis results and reaction activity evaluation according to base type. Yield represents the yield according to CO+CO2 conversion.

[0177]

[0178] Base type S BET (m 2 / g)pore volume (cm 3 / g)X CO+CO2 (%)X CO2 (%)Yield (%)CH4C 2~4 C 5~12 C 13+ NH4HCO398.60.1936.825.91.510.618.06.0(NH4)2CO348.90.129.018.63.07.114.34.6

[0179]

[0180] As shown in [Table 5], the CO2 conversion rate was measured to be 25.9% when NH4HCO3 was added, and 18.6% when (NH4)2CO3 was added.

[0181]

[0182] Figure 5 shows the XRD pattern of the catalyst according to the base type, and a peak corresponding to CeO2 was confirmed at 33.3° and a peak corresponding to Fe2O3 was confirmed at 35.8°.

[0183]

[0184] Figure 6 shows the results of CO2-TPD and CO-TPD analysis of the catalyst according to the base type, and it was found that the amount of CO and CO2 adsorbed in NH4HCO3 was greater than that in (NH4)2CO3.

[0185]

[0186] [Table 5] As shown in Figures 5 and 6, the relatively high pH of (NH4)2CO3 creates an environment conducive to the precipitation of CeO2, resulting in a low surface area and the growth of CeO2 particles. This difference in physical properties also affects the adsorption of CO and CO2 on the catalyst surface, and the reaction activity and CO2 conversion are also found to be low.

[0187]

[0188] <Experimental Example 3> Optimization of Base Addition Amount

[0189] The SSR method is a catalytic synthesis method that utilizes the reaction principle of producing water and salt through a simple acid-base neutralization reaction. It is most important to select the type and amount of base so that each metal salt in an acidic state is well precipitated.

[0190]

[0191] Figure 7 shows the properties of the catalyst according to the amount of base added. The amount of base added affects the properties of the catalyst. In particular, in the SSR method, if NH4HCO3 is added insufficiently or excessively, a small amount will not gel and will become liquid, while an excessive amount will solidify, making it difficult to obtain the final product.

[0192]

[0193] [Table 6] shows the BET analysis results and reaction activity evaluation according to the amount of NH4HCO3 added. Yield represents the yield according to CO+CO2 conversion.

[0194]

[0195] Addition amount S BET (m 2 / g)pore volume (cm 3 / g)X CO+CO2 (%)X CO2 (%)Yield (%)CH4C 2~4 C 5~12C 13+ 1x98.60.1936.825.91.510.618.06.01.6x93.80.1930.323.91.98.814.76.42.5x72.80.1329.018.82.76.712.67.0

[0196]

[0197] As shown in [Table 6], the CO2 conversion rate was measured to be 25.9% when added 1x, 23.9% when added 1.6x, and 18.8% when added 2.5x. This suggests that when the amount of NH4HCO3 added increases during catalyst manufacturing using the SSR method, the catalyst precursor becomes very hard, preventing phase change, and ultimately reducing the amount of catalyst produced, resulting in a drop in CO2 conversion rate.

[0198]

[0199] <Experimental Example 4> Effects according to Fe content

[0200] In order to increase the active site number of the catalyst, the content of Fe, the main metal in the catalyst, was increased by two and three times compared to the previously added amount.

[0201]

[0202] Figure 8 and [Table 7] show the XRD results of the catalyst according to the Fe content. Looking at Figure 8, a peak corresponding to CeO2 was confirmed at 33.3° and a peak corresponding to Fe2O3 was confirmed at 35.9°.

[0203]

[0204] Fe addition amountCatalyst nameCatalyst 2θFWHMCrystallite size (nm)CeO2 / Fe2O3Peak intensity ratio1 timesFeCuK20CeAlFe 0.37 Cu 0.04 K 0.09 Ce 0.03 Al 0.47 35.910.67121.742x2FeCuK20CeAlFe 0.51 Cu 0.08 K 0.06 Ce 0.02 Al 0.33 35.90.5117.11.813 times 3FeCuK20CeAlFe 0.61 Cu 0.06 K 0.05 Ce 0.02 Al 0.26 35.830.3823.01.93

[0205]

[0206] [Table 7] When added 1x, 2θ was measured to be 35.91, FWHM was 0.67, crystallite size was 12 nm, and CeO2 / Fe2O3Peak intensity ratio was 1.74. When added 2x, 2θ was measured to be 35.9, FWHM was 0.51, crystallite size was 17.1 nm, and CeO2 / Fe2O3Peak intensity ratio was 1.81. In addition, when added 3x, 2θ was measured to be 35.83, FWHM was 0.38, crystallite size was 23 nm, and CeO2 / Fe2O3Peak intensity ratio was 1.93.

[0207]

[0208] Figure 9 shows the results of CO2-TPD and H2-TPR analyses of the catalyst according to Fe content. In the case of H2-TPR, it was confirmed that the amount of H2 consumed through reduction decreased as the Fe content increased, and the CO2-TPD analysis showed that the amount of CO2 adsorbed decreased as the Fe content increased.

[0209]

[0210] [Table 8] shows the BET analysis results and reaction activity evaluation according to Fe content. Yield represents the yield according to CO+CO2 conversion.

[0211]

[0212] Fe addition amount Catalyst name Catalyst S BET (m 2 / g)pore volume (cm 3 / g)X CO+CO2 (%)X CO2 (%)Yield (%)CH4C 2~4 C 5~12 C 13+ 1xFeCuK20CeAlFe 0.37 Cu 0.04 K 0.09 Ce 0.03 Al 0.4798.60.1936.825.91.510.618.06.02x2FeCuK20CeAlFe 0.51 Cu 0.08 K 0.06 Ce 0.02 Al 0.33 93.20.1033.721.32.65.722.23.43 times 3FeCuK20CeAlFe 0.61 Cu 0.06 K 0.05 Ce 0.02 Al 0.26 84.70.0930.418.94.34.117.34.7

[0213]

[0214] As shown in [Table 8], the CO2 conversion rate was measured to be 25.9% when added 1x, 21.3% when added 1.6x, and 18.9% when added 2.5x. In addition, as the Fe content increased, the catalyst surface area and pore volume tended to decrease.

[0215]

[0216] [Table 8] As shown in Figures 8 and 9, as the Fe content increases, the dispersion of the active site decreases due to the influence of low surface area, and the CO2 adsorption amount and H2 reduction amount gradually decrease, resulting in a significantly lower CO2 conversion rate of 18.9%.

[0217]

[0218] Figure 10 shows the results of carbon distribution of liquid products according to Fe content. As the particle size of Fe2O3 increases, the hydrogenation effect is added to the reduced site on the metal surface along with CC coupling, resulting in C 13+ It was confirmed that a large amount of the above hydrocarbons were produced. In addition, since the yield of CH4 increases when Fe is added in excess, an appropriate amount of Fe must be added.

[0219]

[0220] <Experimental Example 5> Effects according to CeO2 content

[0221] In order to increase the oxygen vacancy of the catalyst, the effect of the CeO2 content in the catalyst was investigated.

[0222]

[0223] Figure 11 shows TEM images of catalysts according to CeO2 content. (Same magnification 100 nm, 5 nm) (a) is CeO2 10 wt%, (b) is CeO2 20 wt%, and (c) is CeO2 50 wt%. (d) is CeO2 100 wt%, and (e) is a catalyst (FeCuK / 20CeAl) manufactured by the IMP method.

[0224] Looking at Fig. 11, CeO2 (111), (200), (220), (311) planes were confirmed. The average particle size was measured to be 89 nm for CeO2 10 wt%, 250 nm for CeO2 20 wt%, 410 nm for CeO2 50 wt%, and over 500 nm for CeO2 100 wt%. When the CeO2 lattice d-spacing value was calculated through the TEM image, it can be seen that as the CeO2 content increases, many CeO2 (111) and (220) planes are formed. In addition, it can be seen that the shape is agglomerated into round particles by CeO2, and it can be seen that as the CeO2 content increases, the metal mixed particles agglomerated by CeO2 gradually grow larger.

[0225] In the case of CeO2 100 wt%, unlike other catalysts, it was confirmed that the CuO (110) phase (CuO d=0.264 nm) was widely distributed. This is thought to be because CeO2 itself has a relatively low specific surface area, so the dispersion of Fe, Cu, and K was low, and therefore it can be assumed that the Cu metal exists in a largely aggregated state.

[0226] In the case of CeO2, the crystal growth state is clearly different depending on the electronic state of Ce, and is generally in the form of Rod (110), Cube (100), and Octahedral (111). Rod is Ce 3+ Wow Ce 4+ It is formed when the middle, Cube is Ce 3+ It is formed a lot when the Octahedral is Ce 4+ It is formed when.

[0227] It was confirmed that the catalyst manufactured by the IMP method uniquely formed long rod-shaped CeO2 crystals and distributed metal mixed particles around them. In the case of IMP, CeO2-Al2O3 was formed first. 3+ Wow Ce 4+ It can be seen that the metal mixed particles are supported in a mixed state and have a crystal state as shown in Fig. 11.

[0228]

[0229] [Table 9] shows the specific surface analysis according to the CeO2 content of the catalyst.

[0230]

[0231] CeO2 addition amount, catalyst name, catalyst S BET (m 2 / g)t-plot micropore area (m 2 / g)pore volume (cm 3 / g)Pore size (nm)CeO20 wt%FeCuKeAlFe 0.38 Cu 0.04 K 0.09 Al 0.49 15800.153.4CeO210wt%FeCuK10CeAlFe 0.37 Cu 0.04 K 0.09 Ce 0.02 Al 0.48 9900.14.1CeO220wt%FeCuK20CeAlFe 0.37 Cu 0.04 K 0.09 Ce 0.03 Al 0.4798.600.195.6CeO250wt%FeCuK50CeAlFe 0.35 Cu 0.04 K 0.09 Ce 0.08 Al 0.45 303.40.088.6CeO2100 wt%FeCuKCeO2Fe 0.5 Cu 0.06 K 0.14 Ce 0.26 9.32.60.0621

[0232]

[0233] As shown in [Table 9], the specific surface area and pore volume of the catalyst decreased as the CeO2 content increased through the BET analysis.

[0234]

[0235] Figure 12 shows the XRD results of the catalyst according to the CeO2 content. The XRD analysis according to the CeO2 content in the catalyst was confirmed. Looking at Figure 12, a peak corresponding to CeO2 was confirmed at 33.3°, and a peak corresponding to Fe2O3 was confirmed at 35.9°, and it was confirmed that the CeO2 peak grew as the CeO2 content increased.

[0236] In addition, when the area of ​​approximately 32 to 43 theta / degree was enlarged and examined, the Fe2O3 peak shifted to a low angle. This can be assumed to be due to the substitution of electrons between Fe and other transition metals, and it can be seen that the distribution was more evenly distributed by the SSR method.

[0237]

[0238] Figure 13 shows the results of H2-TPR, CO2-TPD, and CO-TPD analyses of catalysts according to CeO2 content. Through thermal decomposition analysis (H2-TPR, CO, and CO2-TPD), differences in gas adsorption analysis results according to CeO2 content were confirmed.

[0239] In the case of H2-TPR, it was confirmed that the H2 consumed by reduction increased as the CeO2 content increased, and in particular, it was observed that reduction occurred at a higher temperature. In the actual CO2 hydrogenation reaction, the reduction is performed at 350 ℃ as a pretreatment, so the FeCuK20CeAl catalyst has the largest reduction amount in the actual reaction. Therefore, the higher the CeO2 content, the higher the reduction needs to be at a higher temperature. However, in the case of the Fe catalyst, if the reduction is performed at 400 ℃ or higher, the Fe 3+ In Fe 0 The phase changes, which causes deactivation in the CO2 hydroxide reaction, so appropriate reduction conditions are required.

[0240] CO and CO2-TPD analyses showed that as CeO2 increased, the amount of adsorbed CO and CO2 increased, and the phenomenon of desorption at relatively high temperatures was confirmed. This means that CeO22 strongly adsorbs CO and CO2, which also contributes to the reaction activity. Although the amount of desorbed CO2 was the highest at 300 ℃, CeO220 wt%, and the total CO and CO2 adsorption amount was not large, the fact that CO2 is easily adsorbed / desorbed freely within the reaction temperature means that product formation is easier.

[0241]

[0242] [Table 10] shows the evaluation of reaction activity according to the CeO2 content of the catalyst. Yield represents the yield according to the conversion of CO+CO2.

[0243]

[0244] CeO2 addition amount catalyst name X CO+CO2 (%)X CO2 (%)Yield (%)CH4C 2~4 C 5~12 C 13+CeO20 wt%FeCuKeAl24.918.11.44.011.87.7CeO23 wt%FeCuK3CeAl26.518.41.64.412.97.6CeO210 wt%FeCuK10CeAl2818.31.56.013.04.0CeO220 wt%FeCuK20CeAl36.825.91.510.718.06.0CeO230 wt%FeCuK30CeAl30.416.73.17.313.03.2CeO250 wt%FeCuK50CeAl2915.52.87.014.54.7CeO2100 wt%FeCuKCeO229.416.81.25.815.37.1

[0245]

[0246] As shown in [Table 10], it was confirmed that the CO2 conversion rate increased as the CeO2 content increased. In particular, when CeO2 was 20 wt%, C2~C4 and C5~C 12 It can be seen that the yields are the highest at 10.7% and 18.0%, respectively.

[0247]

[0248] <Experimental Example 6> Screening of rare earth metal types

[0249] CeO2 is a typical basicity catalyst and a metal oxide that readily adsorbs CO and CO2. In addition to Ce, rare-earth metals were added to confirm the same oxygen vacancy effect, and La and Pr were also added to confirm the catalytic activity.

[0250]

[0251] [Table 11] shows a comparison of reaction activity evaluations by rare earth metal type. Yield represents the yield resulting from CO+CO2 conversion.

[0252]

[0253] Rare earth metal type catalyst name X CO+CO2 (%)X CO2 (%)Yield (%)CH4C 2~4 C 5~12 C 13+CeFeCuK20CeAl36.825.91.510.618.06.0LaFeCuK20LaAl32.724.82.210.816.96.3PrFeCuK20PrAl31.124.12.64.817.16.6

[0254]

[0255] As shown in [Table 11], the CO2 conversion rate of Ce was measured as 25.9%, La as 24.8%, and Pr as 24.1%.

[0256]

[0257] Figure 14 shows the results of H2-TPR, CO2-TPD, and CO-TPD analyses of catalysts according to the type of rare earth metal. La exists as La2O3 oxide, while in the case of Pr, Pr 6+ or Pr 5+ Since it exists as a , relatively many reducing sites can be expected. However, in reality, due to the high oxidation number, there are many sites adjacent to Al and Fe, so the sites for CO or CO2 adsorption are relatively reduced, and thus the adsorption amount in CO2-TPD and CO-TPD is lower than that in Ce.

[0258]

[0259] <Experimental Example 7> Comparison of reaction activity and characteristic analysis according to the type of heterometal

[0260] C 5+ In order to find an effective cocatalyst for the above long-chain reaction, the reaction activity for Co, Zn, and Zr was confirmed.

[0261]

[0262] Figure 15 shows the results of CO2-TPD and H2-TPR analyses of catalysts according to the type of heterometal. The best CO2 adsorption and H2 reduction were confirmed for Ce.

[0263]

[0264] [Table 12] shows the BET analysis results and reaction activity evaluations according to the type of heterometal. Yield represents the yield according to CO+CO2 conversion.

[0265]

[0266] Heterogeneous metal type catalyst name S BET (m 2 / g)pore volume (cm 3 / g)X CO+CO2 (%)X CO2 (%)Yield (%)O / P (C 2~4 )C1C 2~4 =C 2~4 C 5+ CeFeCuK20CeAl98.60.1936.825.94.124.44.765.45.2CoFeCuK20CoAl70.20.133.520.813.78.54.273.62.0 ZrFeCuK20ZrAl79.30.112418.717.85.24.172.91.3ZnFeCuK20ZnAl104.70.1629.422.211.715.19.463.81.6

[0267]

[0268] As shown in [Table 12], there was no significant improvement in CO2 adsorption capacity compared to the case of using Ce, and therefore, there was no significant difference in CO2 conversion rate. However, C of the liquid product 5+ It was confirmed through reaction activity that a large number of the above long-chain products were formed.

[0269] However, the problem is that it was confirmed that a small amount of wax solids were formed within the liquid product, and in the case of wax solids, it is judged to be unsuitable as it may cause operating cost issues in the separation and purification part of the reaction process in the future.

[0270]

[0271] <Experimental Example 8> Evaluation of long-term stability of catalyst

[0272] Long-term stability evaluation was performed using catalysts manufactured by the SSR and CP methods.

[0273]

[0274] Figure 16 shows the results of a long-term stability evaluation of a catalyst manufactured by the SSR method, and Figure 17 shows the results of the carbon distribution of the liquid product during the long-term stability evaluation of the catalyst manufactured by the SSR method. In the case of the catalyst manufactured by the SSR method, it was confirmed that a stable CO2 conversion rate and product yield were observed for 720 h, and the carbon distribution of the recovered liquid product was also almost similar.

[0275]

[0276] Figure 18 shows the carbon distribution results of the liquid product during the long-term stability evaluation of a catalyst manufactured via the CP method. In contrast, the carbon distribution of the liquid product recovered after 352 h of reaction for the CP catalyst differs significantly from that of the liquid product recovered after 65 h of reaction. This can be attributed to reaction activity resulting from catalyst deactivation or a change in catalyst state.

[0277]

[0278] Although the present invention has been described in this specification with specific details and limited examples, these are provided only to help a more general understanding of the present invention, and the present invention is not limited to the above examples, and those skilled in the art to which the present invention pertains can make various modifications and variations based on these descriptions. Therefore, the ideas described in this specification should not be limited to the described examples, and all things that are equivalent or equivalent to the claims below, as well as the claims, are considered to fall within the scope of the ideas described in this specification.

Claims

1. A catalyst for converting carbon dioxide into hydrocarbon, which is a compound represented by the following chemical formula 1. [Chemical Formula 1] Fe a With b K c the d (M) e The 2θ value of the XRD of the above catalyst includes a peak of 35.89 to 35.93, The above M includes at least one selected from rare earth metals including Ce, La, and Pr, The sum of the composition ratios of a, b, c, d, and e above is 1.

2. In paragraph 1, The above hydrocarbons have carbon numbers of C2~C4 and C5~C 12 Catalyst for conversion of carbon dioxide.

3. In paragraph 1, The above catalyst is C 5~12 / Catalyst for carbon dioxide conversion having a CH4 yield ratio of 10 to 15.

4. In paragraph 1, The above catalyst is a catalyst for carbon dioxide conversion having an XRD FWHM (full width at half maximum) value of 0.5 to 0.

7.

5. In paragraph 1, The above catalyst is a catalyst for carbon dioxide conversion having a crystallite size (particle size) of 10 to 20 nm by XRD.

6. In paragraph 1, The above catalyst is a catalyst for carbon dioxide conversion having an XRD (M)O2 / Fe2O3 peak intensity ratio of 1.70 to 1.

85.

7. In paragraph 1, The above catalyst is Fe by XPS 2+ / Fe 3+ A catalyst for carbon dioxide conversion having a ratio of 1.0 to 1.

4.

8. In paragraph 1, The above catalyst is a catalyst for carbon dioxide conversion having a pore volume of 0.17 to 0.21 in BET analysis.

9. In paragraph 8, The above catalyst is S BET 80 to 200 m 2 / g Catalyst for carbon dioxide conversion.

10. In paragraph 1, The above catalyst is a catalyst for carbon dioxide conversion manufactured through a mixing and diffusion reaction by mechanical shear force of each constituent metal salt under solvent-free conditions.

11. In paragraph 10, A catalyst for carbon dioxide conversion, wherein the metal salt comprises at least one compound selected from the group of organic compounds including nitrate, ammonium nitrate, carbonate, bicarbonate, hydroxide, oxide, oxyhydrate, acetate, and sulfate.

12. In paragraph 11, A catalyst for converting carbon dioxide, wherein the metal salt is mixed in an equivalent ratio according to the composition ratio of the chemical formula 1.

13. A catalyst for carbon dioxide conversion represented by the following chemical formula 1, [Chemical Formula 1] Fe a With b K c the d (M) e The above M includes at least one selected from rare earth metals including Ce, La, and Pr, The composition ratios of a, b, c, d and e above are total 1, A step of preparing a catalyst precursor through mixing and diffusion reaction of each constituent metal salt and base by mechanical shear force; and A step of manufacturing a catalyst for carbon dioxide conversion by calcining the above catalyst precursor at high temperature; A method for producing a catalyst for carbon dioxide conversion comprising:

14. In paragraph 13, A method for producing a catalyst for converting carbon dioxide, wherein the metal salt comprises at least one compound selected from the group of organic compounds including nitrate, ammonium nitrate, carbonate, bicarbonate, hydroxide, oxide, oxyhydrate, acetate, and sulfate.

15. In paragraph 14, A method for producing a catalyst for converting carbon dioxide, wherein the above metal salt is mixed in an equivalent ratio according to the composition ratio of the above chemical formula 1.

16. In paragraph 13, The above base is a method for producing a catalyst for converting carbon dioxide, wherein the base comprises at least one base selected from a group containing ammonium ions.

17. In paragraph 16, The above base is NH4HCO3, A method for producing a catalyst for converting carbon dioxide, wherein, in the above chemical formula 1, 3a+2b+c+3d+3e is represented by f, the NH4HCO3 is mixed in an equivalent ratio of f±0.

05.

18. In paragraph 13, A method for producing a catalyst for carbon dioxide conversion, wherein the above-mentioned calcination temperature is 300 to 1000°C.

19. In paragraph 13, A method for producing a catalyst for carbon dioxide conversion, wherein the above-mentioned calcination time is 30 minutes to 20 hours.

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