Carbon dioxide conversion catalyst system using zeolite so as to have improved liquid fuel yield

Abstract

The present invention relates to a carbon dioxide conversion catalyst system using zeolite so as to have improved liquid fuel yield and, specifically, to a carbon dioxide conversion catalyst system using a Si-P-Al-based zeolite so as to have an improved yield of naphtha and gasoline, which are generated by hydrogenation of carbon dioxide.

Description

Catalytic system for carbon dioxide conversion with improved liquid fuel yield utilizing zeolite

[0001] The present invention relates to a catalyst system for carbon dioxide conversion that improves the yield of liquid fuel by utilizing zeolite, and more specifically, to a catalyst system for carbon dioxide conversion that improves the yield of naphtha and gasoline produced by the hydrogenation reaction of carbon dioxide by utilizing Si-P-Al zeolite.

[0002]

[0003] Since the Industrial Revolution, the increased use of fossil fuels like coal and oil has led to an excessive increase in carbon dioxide (CO2) emissions. Carbon dioxide absorbs excessive radiant energy, raising the Earth's temperature, a phenomenon known as global warming. Global warming is causing rising temperatures, rising sea levels, droughts, floods, heat waves, heavy snowfall, and earthquakes, and is also causing physical environmental changes such as ecosystem disruption. It is also having a wide-ranging negative impact on our surroundings, including agriculture, livestock farming, and industrial activities, as well as human health and the living environment.

[0004] Recently, with the global interest in "carbon neutrality," a low-carbon, eco-friendly economy, technologies for capturing and processing carbon dioxide emitted from the atmosphere have been attracting attention from both academia and industry. Consequently, there is growing interest in developing new technologies that separate and recover carbon dioxide, allowing it to be recycled and reincorporated into the current energy and chemical industry systems. One such technology, hydrogenation, has been studied to convert carbon dioxide into alternative petroleum chemicals.

[0005] The applicant of the present invention has conducted research to convert excess carbon dioxide, hydrogen and some carbon monoxide in the process exhaust gas (HMP Purge gas), and through carbon dioxide hydrogenation reaction, converts C2~C4 base oil and C5~C 12We developed an Fe-based FeCuKCeAl catalyst (application number 10-2023-0126884) that can be converted to a naphtha-range fuel.

[0006] However, while the optimal condition for carbon dioxide conversion is a H2 / CO2 molar ratio of 3, the H2 / CO2 molar ratio in the flue gas is less than 2, making carbon dioxide conversion difficult. While additional hydrogen can be added to the flue gas during the refinery process to improve the carbon dioxide conversion rate, adding hydrogen is not cost-effective given the current high price of hydrogen.

[0007] Zeolites have been used to convert carbon dioxide into liquid fuel under these low hydrogen supply conditions, potentially improving the yield of the fuel. However, ZSM-5, a Si-Al zeolite widely used in the past, produces a large amount of CH4 as a byproduct during carbon dioxide conversion, and produces more aromatic hydrocarbons than linear hydrocarbons.

[0008]

[0009] The present invention is intended to solve the problems of the prior art, and to improve the yield of liquid fuel by utilizing Si-P-Al zeolite in carbon dioxide hydrogenation reaction.

[0010]

[0011] A catalyst system for carbon dioxide conversion with improved liquid fuel yield utilizing zeolite according to the present invention comprises an Fe-based catalyst manufactured through a mixing and diffusion reaction by mechanical shearing of a metal precursor under solvent-free conditions; and a zeolite; capable of producing liquid fuel from carbon dioxide.

[0012] The above Fe-based catalyst may be a compound represented by the following [chemical formula 1].

[0013] [Chemical Formula 1]

[0014] Fe a Cu b K c Ald (M) e

[0015] The above M includes at least one selected from rare earth metals including cerium (Ce), lanthanum (La) and praseodymium (Pr), and the a, b, c, d and e have a total of 1 and are independently 0.01 to 0.7.

[0016] The above Fe-based catalyst can be manufactured by mixing each constituent metal precursor in an equivalent ratio according to the above chemical formula 1 and applying mechanical shear force.

[0017] The metal precursor may be a metal salt comprising at least one selected from the group consisting of nitrate, ammonium nitrate, carbonate, bicarbonate, hydroxide, oxide, oxyhydrate, acetate, and sulfate.

[0018] The above Fe-based catalyst may include a peak having a 2θ value of XRD of 35.85 to 35.95.

[0019] The above Fe-based catalyst may have a particle size (crystallite size) of 10 to 20 nm.

[0020] The above Fe-based catalyst has a BET surface area of ​​50 to 200 m 2 / g may be.

[0021] The above Fe-based catalyst has a pore volume of 0.01 to 0.5 cm 3 / g may be.

[0022] The above zeolite may be a silicoaluminophosphate-34 (SAPO-34) zeolite.

[0023] The pore size of the above SAPO-34 may be 1 to 5 Å.

[0024] The acidity of the above SAPO-34 is 1 to 2 mmol / g cat It could be.

[0025] The (Si+P) / Al ratio of the above SAPO-34 may be 0.1 to 1.

[0026] The above Fe-based catalyst and zeolite can be arranged in a dual bed in a single catalytic reactor or sequentially in different catalytic reactors.

[0027] The above Fe-based catalyst and zeolite can be arranged to sequentially contact the introduced gas containing carbon dioxide.

[0028] The mass ratio of the above Fe-based catalyst and zeolite may be 1:0.5 to 5.

[0029] The above liquid fuel has a carbon number of C5~C 12 It could be.

[0030] The carbon dioxide conversion method according to the present invention can produce hydrocarbons by sequentially contacting a gas containing carbon dioxide with the Fe-based catalyst and zeolite using the above carbon dioxide conversion catalyst system.

[0031] The molar ratio of H2 and CO2 in the gas containing the above carbon dioxide may be 1 to 3:1.

[0032] The GHSV (Gas Hourly Space Velocity) of the gas containing the above carbon dioxide may be 1,000 to 10,000 mL / gcat·h.

[0033] In the above carbon dioxide conversion method, the pressure may be 1 to 50 bar.

[0034] In the above carbon dioxide conversion method, the temperature may be 100 to 1000°C.

[0035] In the above carbon dioxide conversion method, the carbon number of the hydrocarbon is C5~C 12 It could be.

[0036]

[0037] According to the present invention, by utilizing Si-P-Al zeolite in carbon dioxide hydrogenation reaction, base oil (C2~C4) produced by reverse water gas shift reaction (RWGS) and Fischer-Tropsch synthesis reaction is oligomerized and long-chain hydrocarbons (C 13+ ) was cracked to improve the yield of naphtha and gasoline.

[0038] In addition, according to the present invention, the Fe-based catalyst manufactured through a mixing and diffusion reaction by mechanical shear force, compared to the conventional co-precipitation or impregnation method, has uniform particles that are evenly dispersed, thereby improving the reaction activity.

[0039]

[0040] Figure 1 shows the composition of an Fe-based catalyst and zeolite according to one embodiment of the present invention.

[0041] Figure 2 shows SEM and EDS mapping images of an Fe-based catalyst according to one embodiment of the present invention.

[0042] Figure 3 shows the XRD results of an Fe-based catalyst according to one embodiment of the present invention.

[0043] Figure 4 shows the XPS results of an Fe-based catalyst according to one embodiment of the present invention.

[0044] Figure 5 shows the reaction activity according to the use of zeolite of the present invention.

[0045] Figures 6 and 7 show the hydrocarbon distribution of the liquid product according to the zeolite of the present invention.

[0046] Figure 8 shows the carbon distribution of the liquid product according to the use of zeolite of the present invention.

[0047]

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] Furthermore, in this specification and the appended claims, terms such as “include” or “have” 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.

[0055] Hereinafter, a catalyst system for converting carbon dioxide with improved liquid fuel yield utilizing the zeolite of the present invention will be described in detail with reference to the attached drawings.

[0056]

[0057] 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).

[0058] [Table 1] shows the uses of products obtained through the hydrogenation reaction of carbon dioxide according to their carbon number range.

[0059]

[0060] 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 materialsC20 -C 40 Paraffin Wax Wax C 40 Excess asphalt, asphalt, tar

[0061]

[0062] A crucial element in the carbon dioxide 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.

[0063] However, the FeCuKAl catalyst, which is widely known as a conventional Fe-based catalyst, had the problem of relatively low carbon dioxide conversion. Therefore, the applicant of the present invention developed an Fe-based FeCuKCeAl catalyst (application number 10-2023-0126884) by applying a rare earth metal as a cocatalyst that facilitates carbon dioxide adsorption and desorption to compensate for the shortcomings of conventional Fe-based catalysts.

[0064] Meanwhile, the molar ratio of H2 / CO2 in the exhaust gas required for the hydrogenation reaction of carbon dioxide is 3, and the reaction pressure also requires 30 to 40 bar. The hydrogenation reaction activity of carbon dioxide at this time is the carbon dioxide conversion rate of 40%, C, as reported so far. 5+ The ideal yield is 20%. While additional hydrogen can be added to improve the carbon dioxide conversion rate and product yield in the carbon dioxide hydrogenation reaction, this is inefficient considering the process cost. Therefore, the development of a catalyst system for carbon dioxide conversion that can achieve the target yield without additional hydrogen is necessary.

[0065] Zeolites are natural and synthetic silicate minerals. Due to their porous structure, in which cavities large enough to adsorb molecules exist regularly within the crystal, zeolites exhibit excellent interfacial activity and possess outstanding catalytic properties. The catalytic properties of zeolites vary depending on the zeolite structure, the nature and structural position of cations, the Si / Al content ratio, and the presence of active metal elements. The catalytic properties of zeolites are utilized in the fields of petroleum refining and petrochemicals. When long-chain hydrocarbons and light olefins are fed as reactants, they can control the carbon chain through cracking and oligomerization, thereby improving the yield of naphtha and gasoline.

[0066] Traditionally, zeolites composed of Si-Al have been widely used as catalysts. However, Si-Al zeolites have the disadvantage of producing a large amount of CH4 as a byproduct during the cracking process due to strong acid sites, causing a decrease in catalytic activity due to coke, and forming more aromatic hydrocarbons than linear hydrocarbons due to their large pore size (5-6 Å).

[0067] To improve the problems of these Si-Al zeolites, Si-P-Al zeolites, which are widely known as MTO (Methanol to Olefin) catalysts, can be utilized. Since the Si-P-Al zeolites have weak acid sites, they can relatively suppress the production of by-products such as coke and CH4, and have the advantage of suppressing the production of aromatic compounds and heavy olefins, thereby increasing the yield of light olefins (C2~C4).

[0068] Accordingly, the present invention aims to improve the yield of naphtha and gasoline, which are liquid fuels, through oligomerization and cracking from the products of carbon dioxide hydrogenation reaction by utilizing Si-P-Al zeolite on an Fe-based catalyst.

[0069]

[0070] The present invention can provide a catalyst system for carbon dioxide conversion, including an Fe-based catalyst manufactured through a mixing and diffusion reaction by mechanical shearing of a metal precursor under solvent-free conditions; and a zeolite.

[0071] As an example, the Fe-based catalyst is a compound represented by the following chemical formula 1, which produces C2~C4 base oil and C5~C through carbon dioxide hydrogenation reaction. 12 It can be converted to a naphtha-range fuel. The previously filed FeCuKCeAl catalyst is described in detail in Korean Patent Application No. 10-2023-0126884.

[0072] [Chemical Formula 1]

[0073] Fe a Cu b K c Al d (M) e

[0074] The above M may include one or more selected from rare earth metals including cerium (Ce), lanthanum (La), and praseodymium (Pr). The above a, b, c, d and e have a total of 1 and are independently 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.3, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.4, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49, 0.5, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.59, 0.6, 0.61, 0.62, 0.63, 0.64, 0.65, 0.66, 0.67, 0.68, 0.69, 0.7 or a range between any two of the values ​​described herein, but is not limited thereto.

[0075] As an example, the Fe-based catalyst can be prepared by mixing each constituent metal precursor in an equivalent ratio according to the above chemical formula 1 and applying mechanical shear force. Preferably, the catalyst can be prepared through mixing and diffusion reaction of each constituent metal precursor by mechanical shear force under solvent-free conditions, and this is called a solid state reaction (SSR) or solid-state reaction method.

[0076] The solid-state method is a reaction in which substances mixed in a pure solid state are converted into new compounds by temperature, pressure, etc., and is simpler to manufacture than the conventional co-precipitation (CP) or impregnation (IMP) method, and can produce catalysts with uniform particles.

[0077] As an example, the mixing method is not particularly limited as long as it is a method commonly used in the art. For example, mixing can be done by hand using a mortar and pestle, or by using a grinding device or ball mill, but this is not a limitation. In particular, using a ball mill allows for mass production with fewer physical variables.

[0078] As an example, the metal precursor may be a metal salt comprising at least one selected from the group consisting of nitrate, ammonium nitrate, carbonate, bicarbonate, hydroxide, oxide, oxyhydrate, acetate, and sulfate. Preferably, the metal precursor may be a metal nitrate, and a hydrate, anhydride, or a mixture thereof may also be used, but is not limited thereto.

[0079] As an example, the Fe-based catalyst can be synthesized using nitrate as a metal precursor and ammonium bicarbonate (NH4HCO3) as a base, as shown in the following chemical formula 2. At this time, it is important to adjust the amounts of each metal precursor and base so that the molar ratio of the base and carbon dioxide becomes 1.

[0080] [Chemical Formula 2]

[0081] Acid + Base → salt↓ + H2O

[0082] ①aFe(NO3)3·9H2O + 3aNH4HCO3→aFeOOH + 3aNH4NO3+ 10aH2O + 3aCO2

[0083] ②bCu(NO3)2·3H2O + 2bNH4HCO3→bCuO + 2bNH4NO3+ 4bH2O + 2bCO2

[0084] ③cKNO3+cNH4HCO3→cKOH +cNH4NO3+cCO2

[0085] ④dAl(NO3)3·9H2O + 3dNH4HCO3→dAlOOH + 3dNH4NO3+ 10dH2O + 3dCO2

[0086] ⑤eCe(NO3)3·6H2O + 3eNH4HCO3→eCeOOH + 3eNH4NO3+ 7eH2O + 3eCO2

[0087] -----------------------------------------------------------------------

[0088] 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

[0089] As an example, the mixture of the metal precursor and the base can be ultimately obtained in the form of a gel as the phase of the material changes from solid-liquid-solid during mixing.

[0090] As an example, the catalyst for carbon dioxide conversion may include a peak having an XRD 2θ value of 35.85, 35.86, 35.87, 35.88, 35.89, 35.90, 35.91, 35.92, 35.93, 35.94, 35.95, or a range between any two of the values ​​described herein. For example, the XRD 2θ value of the peak may be, but is not limited to, 35.85 to 35.95, 35.89 to 35.95, or 35.89 to 35.93.

[0091] As an example, the catalyst for carbon dioxide conversion may have a crystallite size of 10 nm, 11 nm, 12 nm, 13 nm, 14 nm, 15 nm, 16 nm, 17 nm, 18 nm, 19 nm, 20 nm, or a range between any two of the values ​​described herein. For example, the particle size may be, but is not limited to, 10 to 20 nm, 10 to 15 nm, or 12 to 14 nm.

[0092] As an example, the above carbon dioxide conversion catalyst has a BET surface area of ​​50 m 2 / g, 60 m 2 / g, 70 m 2 / g, 80 m 2 / g, 90 m 2 / g, 100 m 2 / g, 110 m 2 / g, 120 m 2 / g, 130 m 2 / g, 140 m 2 / g, 150 m 2 / g, 160 m 2 / g, 170 m 2 / g, 180 m 2 / g, 190 m 2 / g, 200 m 2 / g or may be within a range between any two values ​​described herein. For example, the BET surface area may be from 50 to 200 m 2 / g, 60 to 150 m 2 / g or 65 to 100 m 2 / g may be, but is not limited to, this.

[0093] As an example, the catalyst for converting carbon dioxide has a pore volume of 0.01 cm 3 / g, 0.02 cm 3 / g, 0.03 cm 3 / g, 0.04 cm 3 / g, 0.05 cm3 / g, 0.06 cm 3 / g, 0.07 cm 3 / g, 0.08 cm 3 / g, 0.09 cm 3 / g, 0.1 cm 3 / g, 0.11 cm 3 / g, 0.12 cm 3 / g, 0.13 cm 3 / g, 0.14 cm 3 / g, 0.15 cm 3 / g, 0.16 cm 3 / g, 0.17 cm 3 / g, 0.18 cm 3 / g, 0.19 cm 3 / g, 0.2 cm 3 / g, 0.21 cm 3 / g, 0.22 cm 3 / g, 0.23 cm 3 / g, 0.24 cm 3 / g, 0.25 cm 3 / g, 0.26 cm 3 / g, 0.27 cm 3 / g, 0.28 cm 3 / g, 0.29 cm 3 / g, 0.3 cm 3 / g, 0.31 cm 3 / g, 0.32 cm 3 / g, 0.33 cm 3 / g, 0.34 cm 3 / g, 0.35 cm 3 / g, 0.36 cm 3 / g, 0.37 cm 3 / g, 0.38 cm 3 / g, 0.39 cm 3 / g, 0.4 cm 3 / g, 0.41 cm 3 / g, 0.42 cm 3 / g, 0.43 cm 3 / g, 0.44 cm 3 / g, 0.45 cm 3 / g, 0.46 cm 3 / g, 0.47 cm 3 / g, 0.48 cm 3 / g, 0.49 cm 3 / g, 0.5 cm 3 / g or may be within a range between any two values ​​described herein. For example, the volume of the void may be between 0.01 and 0.5 cm 3 / g, 0.05 to 0.5 cm 3 / g or 0.05 to 0.25 cm 3 / g may be, but is not limited to, this.

[0094] As an example, the zeolite may include a Si-Al zeolite, a Si-P-Al zeolite, or a mixture thereof, and may preferably be silicon aluminophosphate (Silicoaluminophosphate-34, SAPO-34), but is not limited thereto.

[0095] The above SAPO-34 is a molecular sieve with a unique structure in which the P element exists between Si-Al, appropriate acid properties, and excellent stability under various operating conditions. It is characterized by a three-dimensional pore structure forming a unique framework (Chabazite type, CHA), and has the advantage of suppressing the production of aromatic compounds and heavy olefins, thereby increasing the yield of light olefins (C2-C4). In addition, since the strength of the acid site is weaker than that of conventional zeolites, it can relatively suppress the production of byproducts such as coke and CH4.

[0096] As an example, the pore size of the SAPO-34 may be 1 Å, 2 Å, 3 Å, 4 Å, 5 Å, or within a range between any two of the values ​​described herein. For example, the pore size may be, but is not limited to, 1 to 5 Å, 2 to 4 Å, or 3 to 4 Å.

[0097] As an example, the Acidity of the SAPO-34 is 1 mmol / g cat , 1.1 mmol / g cat , 1.2 mmol / g cat , 1.3 mmol / g cat , 1.4 mmol / g cat , 1.5 mmol / g cat , 1.6 mmol / g cat , 1.7 mmol / g cat , 1.8 mmol / g cat , 1.9 mmol / g cat , 2 mmol / g cat Or it may be within a range between any two of the values ​​described herein. For example, the Acidity may be 1 to 2 mmol / g. cat , 1 to 1.5 mmol / g cat or 1 to 1.2 mmol / g cat It may be, but is not limited to,

[0098] As an example, the (Si+P) / Al ratio of the SAPO-34 may be within a range of 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, or any two of the values ​​described herein. For example, the (Si+P) / Al ratio may be, but is not limited to, 0.1 to 1, 0.5 to 0.8, or 0.6 to 0.7.

[0099] Figure 1 shows the composition of an Fe-based catalyst and zeolite according to one embodiment of the present invention.

[0100] As one embodiment, the Fe-based catalyst and zeolite may be arranged in a dual bed (2-bed) within a single catalytic reactor, and as another embodiment, the Fe-based catalyst and zeolite may be arranged sequentially in separate catalytic reactors. Preferably, the zeolite may be arranged in a dual bed within a single catalytic reactor, but is not limited thereto.

[0101] As an example, the Fe-based catalyst and zeolite may be arranged to sequentially contact the introduced gas containing carbon dioxide. Preferably, the gas containing carbon dioxide first reacts on the Fe-based catalyst, and then secondarily oligomerizes the base oil (C2~C4) to increase the carbon number and long-chain hydrocarbons (C 13+ ) is broken down (cracking) into molecules with smaller carbon numbers to produce liquid fuel (C5~C 12 ) can improve the yield.

[0102] As an example, the mass ratio of the Fe-based catalyst and the zeolite may be 1:0.5, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, or within a range between any two of the values ​​described herein. For example, the mass ratio may be, but is not limited to, 1:0.5 to 5, 1:1 to 3, or 1:1 to 2.

[0103] In addition, the present invention utilizes the above carbon dioxide conversion catalyst system to sequentially contact a gas containing carbon dioxide with the Fe-based catalyst and zeolite to produce naphtha and gasoline (C5~C 12 ) can provide a method for converting carbon dioxide with improved yield.

[0104] As an example, the molar ratio of H2 and CO2 of the gas containing the carbon dioxide may be 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, 2:1, 2.1:1, 2.2:1, 2.3:1, 2.4:1, 2.5:1, 2.6:1, 2.7:1, 2.8:1, 2.9:1, 3:1, or within a range between any two of the values ​​described herein. For example, the molar ratio may be, but is not limited to, 1 to 3:1, 1.5 to 2.5:1, or 1.5 to 2:1.

[0105] As an example, the GHSV (Gas Hourly Space Velocity) of the gas containing the carbon dioxide may be 1,000 mL / gcat·h, 2,000 mL / gcat·h, 3,000 mL / gcat·h, 4,000 mL / gcat·h, 5,000 mL / gcat·h, 6,000 mL / gcat·h, 7,000 mL / gcat·h, 8,000 mL / gcat·h, 9,000 mL / gcat·h, 10,000 mL / gcat·h, or within a range between any two of the values ​​described herein. For example, the GHSV may be 1,000 to 10,000 mL / gcat·h, 3,000 to 8,000 mL / gcat·h, or 6,000 to 7,000 mL / gcat·h, but is not limited thereto.

[0106] In the above carbon dioxide conversion method, if the pressure and temperature are too low, the reaction is insufficient and the amount of reaction product produced is small, and if the pressure and temperature are too high, there is a problem of reduced energy efficiency.

[0107] As an example, in the carbon dioxide conversion method, the pressure is 1 bar, 2 bar, 3 bar, 4 bar, 5 bar, 6 bar, 7 bar, 8 bar, 9 bar, 10 bar, 11 bar, 12 bar, 13 bar, 14 bar, 15 bar, 16 bar, 17 bar, 18 bar, 19 bar, 20 bar, 21 bar, 22 bar, 23 bar, 24 bar, 25 bar, 26 bar, 27 bar, 28 bar, 29 bar, 30 bar, 31 bar, 32 bar, 33 bar, 34 bar, 35 bar, 36 bar, 37 bar, 38 bar, 39 bar, 40 bar, 41 bar, 42 bar, 43 bar, 44 bar, 45 bar, 46 bar, 47 bar, 48 bar, The pressure may be within a range of 49 bar, 50 bar, or any two of the values ​​described herein. For example, the pressure may be, but is not limited to, 1 to 50 bar, 10 to 30 bar, or 15 to 25 bar.

[0108] As an example, in the carbon dioxide conversion method, the temperature may be 100°C, 150°C, 200°C, 250°C, 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C, 650°C, 700°C, 750°C, 800°C, 850°C, 900°C, 950°C, 1000°C, or within a range between any two of the values ​​described herein. For example, the temperature may be, but is not limited to, 100 to 1000°C, 200 to 500°C, or 250 to 350°C.

[0109] According to the present invention, by utilizing Si-P-Al zeolite in carbon dioxide hydrogenation reaction, base oil (C2~C4) produced by reverse water gas shift reaction (RWGS) and Fischer-Tropsch synthesis reaction is oligomerized and long-chain hydrocarbons (C 13+ ) was cracked to improve the yield of naphtha and gasoline.

[0110]

[0111] Hereinafter, specific examples of experiments will be provided and explained. However, the experimental examples described below are only illustrative, and the technology described in this specification is not limited thereto.

[0112]

[0113] <Manufacturing Example> Manufacturing of Fe-based catalyst (FeCuK20CeAl)

[0114] 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. During mixing, the mixture changed phases from solid to liquid to solid, and was mixed until it finally became a gel, and then calcined at 400°C for 5 hours to obtain an Fe-based catalyst (Fe 0.37 Cu 0.04 K 0.09 Ce 0.034 Al 0.47 ) was synthesized.

[0115]

[0116] <Reaction driving conditions>

[0117] At atmospheric pressure, H2 / CO=2 was supplied, and reduction treatment was performed at 350 ℃, heating rate 5 ℃ / min for 5 hours, and carbon dioxide hydrogenation reaction was performed at H2 / CO=1.6, 300 ℃, 20 bar, GHSV -1The reaction was performed at a space velocity of 6250 mL / gcat·h. The reactants and products were analyzed online using a gas chromatograph (Agilent Instruments 6890M).

[0118]

[0119] <Example>

[0120] In a down flow stainless steel fixed bed reactor with an inner diameter of 3 / 8” and a length of 40.7 mm, 0.6 g of powdered zeolite (ZSM-5(400)) was first charged to the lower bed, and then 0.6 g of powdered Fe-based catalyst (FeCuK20CeAl) was sequentially charged to the upper bed (mass ratio 1:1).

[0121]

[0122] <Comparative Example>

[0123] The same procedure was followed as in the above example except that ZSM-5 (average pore size of 5.5 Å) was used as the zeolite (mass ratio 1:1).

[0124]

[0125] <Experimental Example 1> Analysis of Fe-based catalysts

[0126] The Fe-based catalyst (FeCuK20CeAl) manufactured in the above manufacturing example was analyzed.

[0127] Figure 2 shows SEM and EDS mapping images of an Fe-based catalyst according to one embodiment of the present invention. It was confirmed that the Fe-based catalyst had a high metal dispersion and a small particle size.

[0128]

[0129] Catalyst nameCatalyst2θFWHMCrystallite size (nm)CeO2 / Fe2O3Peak intensity ratioFeCuK20CeAlFe 0.37 Cu 0.04 K 0.09 Ce 0.034 Al 0.4735.910.67121.74

[0130]

[0131] Figure 3 and Table 2 show the XRD results of an Fe-based catalyst according to one embodiment of the present invention. A peak corresponding to CeO2 was confirmed at 33.3°, and a peak corresponding to Fe2O3 was confirmed at 35.9°. The 2θ of the Fe-based catalyst 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.

[0132] Figure 4 shows the XPS results of an Fe-based catalyst according to one embodiment of the present invention. The influence of the dispersion state of each metal is Fe. 2+ Wow Fe 3+ It is a mixed form. The Fe of the above Fe-based catalyst 2+ / Fe 3+ The ratio was measured as 1.2.

[0133]

[0134] Catalyst NameCatalyst X CO+CO2 (%)Yield (%)C 5~12 / CH4yield ratioCH4C 2~4 C 5~12 C 13+ FeCuK20CeAlFe 0.37 Cu 0.04 K 0.09 Ce 0.034 Al 0.47 36.81.510.618.06.012.0

[0135]

[0136] Table 3 shows the reaction activity of an Fe-based catalyst according to one embodiment of the present invention. Yield represents the yield according to CO+CO2 conversion. The CO2 conversion rate of the Fe-based catalyst is 25.9%, and C 5~12 / CH4yield ratio was measured as 12.0.

[0137] Therefore, it was confirmed that the Fe-based catalyst manufactured through mixing and diffusion reaction by mechanical shear force, compared to the conventional co-precipitation or impregnation method, had evenly dispersed uniform particles and thus had improved reaction activity.

[0138]

[0139] <Experimental Example 2> Comparison by Zeolite Type

[0140] The reaction activities of the Fe catalyst (FeCuK20CeAl), comparative example (Fe-based catalyst + ZSM-5 dual bed), and example (Fe-based catalyst + SAPO-34 dual bed) were evaluated. The average pore size of SAPO-34 is 3.8 Å, and the average pore size of ZSM-5 is 5.5 Å.

[0141]

[0142] Catalyst X CO+CO2 (%X CO2 (%)SelectivityC1C 2~4 = C 2~4 C5 = C5C 6+ FeCuK20CeAl36.825.94.124.44.70.30.664.5Comparative Example27.017.311.56.09.30.60.369.6Example36.328.96.86.68.20.20.477.8

[0143]

[0144] Table 4 and Figure 5 show the reaction activity according to the use of zeolite of the present invention. C when Fe-based catalyst and zeolite were used in a dual bed was higher than when Fe-based catalyst alone was used. 6+ It was confirmed that the selectivity of CH4 increased. However, in the comparative example, there was a problem that the selectivity of CH4 increased by about 2.5 times due to the effect of cracking by acid sites. Therefore, it was confirmed that the reaction activity was the best in the example using the Fe-based catalyst and SAPO-34 as a dual bed.

[0145] Figures 6 and 7 show the hydrocarbon distribution of the liquid product according to the zeolite of the present invention. The liquid product (C4~C 10 ) was analyzed by Reformulyzer. (a) is a comparative example, and (b) is an example. (a) shows that the aromatic compound produced is 17%, while (b) shows 4.2%, which is significantly less than that of ZSM-5. This is thought to be because aromatic compounds were not formed during the oligomerization process due to the pore specificity of SAPO-34.

[0146] Figure 8 shows the carbon distribution of the liquid product according to the use of zeolite of the present invention, (a) is an Fe-based catalyst, and (b) is an example. Among the liquid products of (a), C5~C 12 The specific gravity of (b) is 74.6%, and C5~C among the liquid products 12 The specific gravity of C5~C is 81.5%, which is higher than that of (a) in the liquid product. 12 It was confirmed that the proportion increased by approximately 7%.

[0147]

[0148] 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 system for converting carbon dioxide to produce liquid fuel from carbon dioxide, comprising an Fe-based catalyst prepared through a mixing and diffusion reaction by mechanical shearing of a metal precursor under solvent-free conditions; and a zeolite.

2. In paragraph 1, The above Fe-based catalyst is a catalyst system for carbon dioxide conversion, 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 above M includes at least one selected from rare earth metals including cerium (Ce), lanthanum (La), and praseodymium (Pr), and the a, b, c, d, and e have a total sum of 1 and are independently 0.01 to 0.

7.

3. In paragraph 2, The above Fe-based catalyst is a catalyst system for carbon dioxide conversion manufactured by mixing each component metal precursor in an equivalent ratio according to the above chemical formula 1 and applying mechanical shear force.

4. In paragraph 3, A catalyst system for carbon dioxide conversion, wherein the metal precursor is a metal salt including at least one selected from the group consisting of nitrate, ammonium nitrate, carbonate, bicarbonate, hydroxide, oxide, oxyhydrate, acetate, and sulfate.

5. In paragraph 2, The above Fe-based catalyst is a catalyst system for carbon dioxide conversion including a peak having an XRD 2θ value of 35.85 to 35.

95.

6. In paragraph 2, The above Fe-based catalyst is a catalyst system for carbon dioxide conversion having a particle size (crystallite size) of 10 to 20 nm.

7. In paragraph 2, The above Fe-based catalyst has a BET surface area of ​​50 to 200 m 2 / g Catalytic system for carbon dioxide conversion.

8. In paragraph 2, The above Fe-based catalyst has a pore volume of 0.01 to 0.5 cm 3 / g Catalytic system for carbon dioxide conversion.

9. In paragraph 1, The above zeolite is a catalyst system for carbon dioxide conversion, which is a silicoaluminophosphate (SAPO-34) zeolite.

10. In paragraph 9, The above SAPO-34 is a catalyst system for carbon dioxide conversion having a pore size of 1 to 5 Å.

11. In paragraph 9, The Acidity of the above SAPO-34 is 1 to 2 mmol / g cat Catalytic system for carbon dioxide conversion.

12. In paragraph 9, A catalyst system for carbon dioxide conversion having a (Si+P) / Al ratio of the above SAPO-34 of 0.1 to 1.

13. In paragraph 1, A catalyst system for carbon dioxide conversion wherein the above Fe-based catalyst and zeolite are arranged in a dual bed in a single catalyst reactor or sequentially in different catalyst reactors.

14. In paragraph 13, A catalyst system for carbon dioxide conversion, wherein the above Fe-based catalyst and zeolite are arranged to sequentially contact a gas containing introduced carbon dioxide.

15. In paragraph 1, A catalyst system for carbon dioxide conversion, wherein the mass ratio of the Fe-based catalyst and zeolite is 1:0.5 to 5.

16. In paragraph 1, The above liquid fuel has a carbon number of C 5 ~C 12 Catalytic system for carbon dioxide conversion.

17. A method for converting carbon dioxide by sequentially contacting a gas containing carbon dioxide with the Fe-based catalyst and zeolite using the carbon dioxide conversion catalyst system of any one of claims 1 to 16 to produce hydrocarbons.

18. In paragraph 17, H of the gas containing the above carbon dioxide 2 and CO 2 A method for converting carbon dioxide in which the molar ratio is 1 to 3:

1.

19. In paragraph 17, A method for converting carbon dioxide, wherein the GHSV (Gas Hourly Space Velocity) of the gas containing the carbon dioxide is 1,000 to 10,000 mL / gcat·h.

20. In paragraph 17, A carbon dioxide conversion method wherein the pressure in the above carbon dioxide conversion method is 1 to 50 bar.

21. In paragraph 17, A carbon dioxide conversion method in which the temperature is 100 to 1000 ℃.

22. In paragraph 17, In the above carbon dioxide conversion method, the carbon number of the hydrocarbon is C 5 ~C 12 A method for converting carbon dioxide into human.

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