Fuel production apparatus

Abstract

Provided is a fuel production device capable of efficiently producing synthetic fuel with a high selectivity of carbon atoms of 5 to 20. One embodiment of the present invention relates to a fuel production device including a ceramic substrate and a catalyst layer. The ceramic substrate defines a gas flow path. A raw material gas containing a carbon oxide and hydrogen is supplied to the gas flow path. The catalyst layer is provided on a surface of the ceramic substrate so as to face the gas flow path. The catalyst layer includes a first catalyst and a second catalyst. The first catalyst is capable of promoting a Fischer-Tropsch reaction. The second catalyst is capable of promoting a hydrocracking reaction and / or an isomerization reaction of a hydrocarbon compound gas produced by the Fischer-Tropsch reaction.

Description

Technical Field

[0001] This invention relates to fuel manufacturing apparatus. Background Technology

[0002] In recent years, from the perspective of reducing environmental impact, research has been conducted on the recovery of carbon oxides containing carbon dioxide and / or carbon monoxide for use as feedstock for hydrocarbon fuels.

[0003] For example, it is known that a hydrocarbon compound containing n-chain alkanes (straight-chain alkanes) is produced from carbon monoxide and hydrogen via a Fischer-Tropsch reaction (hereinafter referred to as the FT reaction), and then the hydrocarbon compound is hydrocracking / isomerized to produce a synthetic fuel with an increased proportion of hydrocarbons in the target range.

[0004] As a method for manufacturing such synthetic fuels, for example, a method has been proposed to synthesize straight-chain hydrocarbons by contacting a synthesis gas of hydrogen and carbon monoxide with a Fischer-Tropsch synthesis catalyst, and to synthesize lower isoalkanes such as isoalkanes by contacting the straight-chain hydrocarbons with a mixture of a hydrogenation catalyst and a solid acid catalyst (see, for example, Patent Document 1).

[0005] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2001-288123 Summary of the Invention

[0006] The technical problem that the invention aims to solve In recent years, research has been conducted on using synthetic fuels, synthesized from carbon oxides and hydrogen, as alternative fuels to petroleum, such as gasoline, diesel, and aviation fuel. To use synthetic fuels as these alternatives, it is necessary to significantly increase the proportion of hydrocarbons (hereinafter sometimes referred to as liquid fuel components) with 5 to 20 carbon atoms in the synthetic fuel.

[0007] However, in the method for synthesizing lower isoalkanes described in Patent Document 1, the produced hydrocarbons do not have sufficient liquid fuel components with 5 to 20 carbon atoms, resulting in the inability to stably produce synthetic fuels suitable as petroleum substitutes.

[0008] The main objective of this invention is to provide a fuel manufacturing apparatus capable of efficiently producing synthetic fuels with an excellent selectivity rate (hereinafter referred to as C5-C20 selectivity) for liquid fuel components with 5 to 20 carbon atoms.

[0009] Technical solutions for solving technical problems [1] One embodiment of the present invention relates to a fuel manufacturing apparatus comprising a ceramic substrate and a catalyst layer. The ceramic substrate defines a gas flow path. A feed gas containing carbon oxides and hydrogen is supplied to the gas flow path. The catalyst layer is disposed on the surface of the ceramic substrate facing the gas flow path. The catalyst layer comprises a first catalyst and a second catalyst. The first catalyst is capable of promoting a Fischer-Tropsch reaction. The second catalyst is capable of promoting a hydrocracking reaction and / or isomerization reaction of the hydrocarbon compound gas generated by the Fischer-Tropsch reaction.

[0010] [2] In the fuel manufacturing apparatus described in [1] above, the thermal conductivity of the ceramic substrate can be 0.4 W / m·K or higher.

[0011] [3] In the fuel manufacturing apparatus described in [1] or [2] above, the catalyst layer may have a single-layer structure in which the first catalyst and the second catalyst are dispersed.

[0012] [4] In the fuel manufacturing apparatus described in [1] or [2] above, the catalyst layer may have a stacked structure, the stacked structure comprising a first catalyst layer containing the first catalyst and a second catalyst layer containing the second catalyst.

[0013] [5] In any of the fuel manufacturing apparatuses described in [1] to [4] above, the ceramic substrate may be a honeycomb substrate. The honeycomb substrate has partitions forming a plurality of pores. At least a portion of the plurality of pores includes the gas flow path described above. The catalyst layer is disposed on the surface of the partitions.

[0014] [6] In the fuel manufacturing apparatus described in [5] above, the porosity of the partition wall may be 65% or less.

[0015] [7] In the fuel manufacturing apparatus described in [5] or [6] above, the porosity of the partition wall may be 10% or less.

[0016] [8] In any one of [5] to [7] above, the thickness of the partition wall may be 0.0635 mm or more and 1.27 mm or less. The pore density in the honeycomb substrate may be 50 cpsi or more and 900 cpsi or less.

[0017] [9] In any of the above-mentioned fuel manufacturing apparatus [1] to [8], the above-mentioned raw material gas may contain carbon monoxide as the above-mentioned carbon oxide.

[0018]

[10] In any of the fuel manufacturing apparatus described in [1] to [9] above, the feed gas may contain carbon dioxide as the carbon oxide. In this case, the catalyst layer contains a third catalyst. This third catalyst is capable of promoting the reverse conversion reaction that converts carbon dioxide into carbon monoxide.

[0019]

[11] In any of the fuel manufacturing apparatuses described in [1] to

[10] above, the catalyst layer may further comprise a packing material. The thermal conductivity of the packing material may be from 0.1 W / m·K to 500 W / m·K.

[0020] Invention Effects According to embodiments of the present invention, synthetic fuels can be produced efficiently with excellent C5 to C20 selectivity. Attached Figure Description

[0021] Figure 1 This is a simplified cross-sectional view of a fuel manufacturing apparatus according to one embodiment of the present invention.

[0022] Figure 2 This is a simplified cross-sectional view of a fuel manufacturing apparatus according to another embodiment of the present invention.

[0023] Figure 3 This is a simplified cross-sectional view of a fuel manufacturing apparatus according to another embodiment of the present invention.

[0024] Figure 4 This is a simplified perspective view of a fuel manufacturing apparatus according to another embodiment of the present invention.

[0025] Figure 5 yes Figure 4 A simplified cross-sectional view of the fuel manufacturing unit.

[0026] Figure 6 This is a simplified cross-sectional view of a fuel manufacturing apparatus according to another embodiment of the present invention.

[0027] Figure 7 This is a simplified cross-sectional view of a fuel manufacturing apparatus according to another embodiment of the present invention. Detailed Implementation

[0028] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited to these embodiments. Furthermore, in order to make the description clearer, the drawings may schematically show the width, thickness, shape, etc. of each part compared to the embodiments, but this is merely an example and does not limit the interpretation of the present invention.

[0029] A. Overview of the fuel production facility like Figure 1As shown, in one embodiment, the fuel manufacturing apparatus 100 includes a ceramic substrate 3 and a catalyst layer 1. The ceramic substrate 3 defines a gas flow path 4. A feed gas containing carbon oxides and hydrogen is supplied to the gas flow path 4. Examples of carbon oxides include carbon monoxide (CO) and carbon dioxide (CO2). The feed gas typically contains carbon monoxide.

[0030] Catalyst layer 1 is disposed on the surface of ceramic substrate 3 facing the gas flow path 4. Catalyst layer 1 includes a first catalyst capable of promoting the FT reaction and a second catalyst capable of promoting the hydrocracking and / or isomerization reaction of the hydrocarbon compounds generated by the FT reaction.

[0031] The inventors have discovered that the flow of feedstock gas through a gas flow path affects the C5-C20 selectivity in synthetic fuels. Therefore, the inventors conducted in-depth research on the flow of feedstock gas in the gas flow path and found that by configuring a first catalyst and a second catalyst to ensure uniform and smooth flow of the feedstock gas, the C5-C20 selectivity in the manufactured synthetic fuels can be improved.

[0032] More specifically, the catalyst layer containing the first catalyst and the second catalyst is disposed on the surface of the ceramic substrate in a manner facing the gas flow path. Therefore, compared with the case where the gas flow path is filled with catalyst particles, the raw material gas passes through the gas flow path uniformly and smoothly, and comes into appropriate contact with the first catalyst and the second catalyst.

[0033] Therefore, the FT reaction shown in equation (1) proceeds smoothly, producing alkanes from carbon monoxide and hydrogen (C2O3). n H 2n+2 Hydrocarbon compounds. In C n H 2n+2 In this context, n represents an integer greater than or equal to 1.

[0034] nCO + (2n+1)H₂ → C n H 2n+2 +nH2O···(1) The hydrocarbon compound contains straight-chain alkanes (5-100 carbon atoms) as its main component. These straight-chain alkanes allow for efficient flow of the feed gas in the gas flow path, improving the uniformity of the feed gas flow. Therefore, through hydrocracking and / or isomerization reactions promoted by a second catalyst, they are fully converted into liquid fuel components with 5-20 carbon atoms. This enables an improved C5-C20 selectivity, allowing for the efficient production of synthetic fuels suitable as petroleum alternatives.

[0035] The thermal conductivity of the ceramic substrate 3 is, for example, 0.4 W / m·K or higher, preferably 0.8 W / m·K or higher, more preferably 8.0 W / m·K or higher, even more preferably 50 W / m·K or higher, and particularly preferably 140 W / m·K or higher. On the other hand, the upper limit of the thermal conductivity of the ceramic substrate 3 is typically 500 W / m·K.

[0036] The aforementioned FT reaction, hydrocracking reaction, and isomerization reaction are all representative exothermic reactions. Therefore, if these reactions are carried out while feedstock gases are being supplied to the gas flow path, a temperature gradient will occur due to the heat of reaction, with the temperature decreasing from the upstream side to the downstream side of the feedstock gas supply direction. In the FT reaction, the reaction products can vary depending on the temperature conditions. In particular, in the high-temperature region where Co catalysts operate at 300°C and Fe catalysts operate at over 350°C, the selectivity for methane increases in the FT reaction, while the selectivity for n-chain alkanes with 5 or more carbon atoms may decrease. Thus, as the selectivity for carbon atoms 5 or more decreases, the amount of liquid fuel components with 5 to 20 carbon atoms produced also decreases.

[0037] In contrast, according to one embodiment, since the thermal conductivity of the ceramic substrate is within the aforementioned range, the ceramic substrate allows for rapid diffusion of the heat of reaction, thereby improving the heat homogenization in the gas flow path. As a result, the temperature can be appropriately controlled throughout the entire gas flow path, ensuring sufficient selectivity for hydrocarbons with 5 or more carbon atoms in the FT reaction. Thus, a stable increase in C5 to C20 selectivity can be achieved.

[0038] The ceramic substrate 3 is composed of any suitable ceramic material.

[0039] Examples of ceramic materials include cordierite, SiC, Si-SiC composites, mullite, alumina, spinel, silicon carbide-cordierite composites, lithium aluminum silicate, aluminum titanate, silicon nitride, and zirconium oxide. Ceramic materials can be used alone or in combination.

[0040] As the material for ceramic substrate 3, ceramic materials are preferred, cordierite, SiC, and Si-SiC composite materials are more preferred, and Si-SiC composite materials are even more preferred.

[0041] Si-SiC composite materials can be either porous or dense. Porous Si-SiC composite materials are described in detail, for example, in Japanese Patent Application Publication No. 2002-201082. Dense Si-SiC composite materials are described in detail, for example, in Japanese Patent Application Publication No. Hei 11-035376. The entire contents of these publications are incorporated herein by reference.

[0042] In Si-SiC composite materials, dense bodies are preferred. If the ceramic substrate is composed of a dense body of a Si-SiC composite material, the thermal conductivity of the ceramic substrate can be stably adjusted within the aforementioned range.

[0043] The catalyst layer 1 can have a single-layer structure or a stacked structure.

[0044] like Figure 1 As shown, in the case where catalyst layer 1 has a single-layer structure, a first catalyst and a second catalyst are dispersed in catalyst layer 1. Based on this configuration, compared to the case where the catalyst layer has a stacked structure, the C5-C20 selectivity in the manufactured synthetic fuel can be stably improved.

[0045] In addition, such as Figure 2 As shown, when the catalyst layer 1 has a stacked structure, the catalyst layer 1 includes a first catalyst layer 11 containing a first catalyst and a second catalyst layer 12 in which a second catalyst is dispersed. In the example shown, the second catalyst layer 12 is stacked on the surface of the ceramic substrate 3. The first catalyst layer 11 is stacked on the surface of the second catalyst layer 12 opposite to the ceramic substrate 3. Thus, the first catalyst layer 11 is arranged facing the gas flow path 4.

[0046] Furthermore, the stacking order of the first catalyst layer 11 and the second catalyst layer 12 can also be reversed. For example... Figure 3 As shown, alternatively, a first catalyst layer 11 may be stacked on the surface of the ceramic substrate 3, and a second catalyst layer 12 may be stacked on the surface of the first catalyst layer 11 opposite to the ceramic substrate 3. In this case, the second catalyst layer 12 is positioned facing the gas flow path 4.

[0047] It should be noted that, in Figure 4 to Figure 7 For convenience, the catalyst layer is illustrated as a single-layer structure. However, in the fuel manufacturing apparatus described below, the catalyst layer may have either a single-layer structure or a stacked structure.

[0048] B. Details of the fuel production facility Next, refer to Figure 1 to Figure 7 The details of fuel manufacturing devices 100, 101 and 102 are described.

[0049] B-1. Details of the fuel manufacturing unit 100 like Figure 1 As shown, the fuel manufacturing apparatus 100 has a flow-through structure.

[0050] In one embodiment, the fuel manufacturing apparatus 100 has a cylindrical substrate 3a as a ceramic substrate 3, the cylindrical substrate 3a having a cylindrical shape extending in a predetermined direction.

[0051] The cylindrical substrate 3a has any suitable shape in its cross-section in a direction orthogonal to the length direction. Examples of cross-sectional shapes for the cylindrical substrate 3a include triangles, quadrilaterals, pentagons, polygons of more than one hexagon, circles, and ellipses.

[0052] The cylindrical substrate 3a includes a gas flow path 4. The gas flow path 4 is a space formed inside the cylindrical substrate 3a. In one embodiment, the gas flow path 4 is formed in the portion of the cross-section of the cylindrical substrate 3a where the catalyst layer 1 is not formed (typically the central portion). The gas flow path 4 extends from a first end face E1 (inflow end face) of the fuel manufacturing apparatus to a second end face E2 (outflow end face). The gas flow path 4 has any suitable shape in a cross-section in a direction orthogonal to the length direction. As a cross-sectional shape of the gas flow path 4, the same cross-sectional shape as that of the cylindrical substrate 3a described above can be cited.

[0053] The cylindrical substrate 3a is configured to be substantially impermeable to synthetic fuel gas.

[0054] The thickness of the cylindrical substrate 3a is, for example, 0.1 mm to 10 mm, or, for example, 0.2 mm to 8 mm, or, for example, 0.5 mm to 5 mm. It should be noted that the thickness is measured, for example, by cross-sectional observation using a SEM (scanning electron microscope).

[0055] The average pore size of the cylindrical substrate 3a is, for example, 0.05. m m~1000 m m. It should be noted that the average pore size is determined, for example, by mercury porosimetry.

[0056] The porosity of the cylindrical substrate 3a is, for example, 0% to 50%. It should be noted that the porosity can be determined, for example, by mercury porosimetry.

[0057] In a cylindrical substrate, if the average pore size and / or porosity are within such a range, it is possible to suppress the leakage of synthetic fuel through the gas flow path from the cylindrical substrate.

[0058] In one embodiment, the catalyst layer 1 is disposed on the inner surface of the cylindrical substrate 3a. The catalyst layer 1 may be disposed on the entire inner surface of the cylindrical substrate 3a or on a portion thereof.

[0059] As described above, catalyst layer 1 comprises a first catalyst and a second catalyst.

[0060] The first catalyst typically contains any suitable active ingredient. Examples of active ingredients include transition metals, noble metals, rare earth elements, alkali metals, and alkaline earth metals. Active ingredients can be used alone or in combination.

[0061] Examples of transition metals include Co, Fe, Ni, Ru, Os, Mn, Cu, Ta, Mo, Zn, Cr, Re, V, Zr, and Ir, with Fe, Co, Ni, and Ru being preferred. Examples of noble metals include Pt, Pd, and Ru. Examples of rare earth elements include La and Ce. Examples of alkali metals include Li, Na, K, and Rb. Examples of alkaline earth metals include Ca, Ba, and Sr.

[0062] The first catalyst may contain these elements in a metallic state (e.g., pure metal, alloy) or in a compound state (e.g., oxide, carbide).

[0063] The preferred first catalyst uses a transition metal, such as Co, Fe, Ni, or Ru, either alone or in combination. If the first catalyst contains at least one or more preferred transition metals, the aforementioned hydrocarbon compounds can be generated more stably from the feed gas.

[0064] In one embodiment, the first catalyst comprises Co and / or Fe. If the first catalyst comprises Co and / or Fe, the activity of the first catalyst can be improved.

[0065] In one embodiment, the first catalyst comprises a transition metal and an alkali metal. With this configuration, the first catalyst, in addition to promoting the FT reaction, can also promote the reverse conversion reaction, which converts carbon dioxide to carbon monoxide. Therefore, hydrocarbon compounds with excellent C5-C20 selectivity can be readily generated from carbon dioxide (CO2) and hydrogen.

[0066] Examples of combinations of transition metals and alkali metals include Co and K, and Fe and Na.

[0067] More specifically, alkali metals (such as K and Na) function as adsorption sites for carbon dioxide, transition metals (such as transition metal oxides such as CoO and Fe3O4) promote the reverse conversion reaction that converts carbon dioxide into carbon monoxide, and transition metals (such as transition metals such as Co and / or transition metal carbides such as Fe5C2) promote the FT reaction.

[0068] When the first catalyst contains a transition metal and an alkali metal, the proportion of the alkali metal relative to 100 parts by mass of the transition metal is, for example, 0.5 to 20 parts by mass, preferably 1 to 10 parts by mass.

[0069] In addition to the active ingredients mentioned above, the first catalyst may also include a support. The support is capable of loading the active ingredients. The support is composed of any suitable inorganic material depending on the application. Examples of inorganic materials include inorganic oxides such as mesoporous materials, carbon materials such as carbon nanotubes and nanoporous carbon, and zeolites. Inorganic materials can be used alone or in combination.

[0070] In one embodiment, the carrier is composed of inorganic oxides.

[0071] Examples of inorganic oxides include aluminum oxide, silicon oxide, magnesium oxide, titanium oxide, cerium oxide, zirconium oxide, and their composite oxides.

[0072] Among inorganic oxides, silicon oxide is preferred.

[0073] The BET specific surface area of ​​such a carrier is, for example, 10 m². 2 / g~1500m 2 / g, preferably 30m 2 / g~1200m 2 / g, more preferably 60m 2 / g~1000m 2 / g. If the BET specific surface area of ​​the support is within this range, the support can be loaded in a state that allows the active components to be fully dispersed, which can further improve the activity of the first catalyst.

[0074] The fine pore size of the carrier is, for example, 3nm~50nm, preferably 5nm~40nm, and more preferably 7nm~30nm.

[0075] The pore volume of the carrier is, for example, 0.1 cc / g to 4 cc / g, preferably 0.2 cc / g to 3.0 cc / g, and more preferably 0.3 cc / g to 2.0 cc / g. It should be noted that the pore volume is determined, for example, by mercury porosimetry or water titration.

[0076] When the first catalyst contains an active ingredient and a support, the proportion of the active ingredient in the first catalyst relative to 100 parts by mass of the support is, for example, 1 to 30 parts by mass, preferably 5 to 20 parts by mass. If the proportion of the active ingredient is within this range, the FT reaction can be stably promoted.

[0077] The first catalyst is typically granular. In one embodiment, the first catalyst is contained as secondary particles in a catalyst layer 1 or a first catalyst layer 11 having a monolayer structure. The average secondary particle size of the first catalyst is, for example, 0.01 mm. m m~100 m m, preferably 0.1 m m~10 m m.

[0078] Examples of secondary catalysts include zeolites, silica-alumina, silica, alumina, titanium dioxide, vanadium oxide, and molybdenum oxide. Secondary catalysts can be used alone or in combination.

[0079] In one embodiment, the second catalyst comprises a zeolite. If the second catalyst comprises a zeolite, it enables the hydrocarbon compound to undergo stable hydrocracking and / or isomerization.

[0080] Examples of zeolites include β-type zeolite, ZSM-5 type zeolite, USY type zeolite, and mordenite type zeolite, with ZSM-5 type and β-type zeolite being preferred.

[0081] The maximum number of rings in the zeolite is, for example, 6 to 16, preferably 8 to 14, and more preferably 10 to 12.

[0082] Zeolites contain SiO2 and Al2O3. The molar ratio of SiO2 to Al2O3 in the zeolite is, for example, 5 to 2000, preferably 10 to 1500. If the molar ratio of SiO2 to Al2O3 in the zeolite is within this range, hydrocarbon compounds can be subjected to hydrocracking and / or isomerization more stably. It should be noted that the molar ratio of SiO2 to Al2O3 is determined, for example, by scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDX; X-ray accelerating voltage 10 kV).

[0083] The second catalyst is typically granular. In one embodiment, the second catalyst is contained as secondary particles in catalyst layer 1 or second catalyst layer 12 having a monolayer structure. The average secondary particle size of the second catalyst is, for example, 0.01 mm. m m~100 m m, preferably 0.1 m m~10 m m.

[0084] When catalyst layer 1 has a single-layer structure, the content of the first catalyst in catalyst layer 1 is, for example, 30% to 95% by mass, preferably 30% to 70% by mass. If the content of the first catalyst is in such a range, the above-mentioned hydrocarbon compound can be generated more stably from the feed gas.

[0085] When catalyst layer 1 has a monolayer structure, the proportion of the second catalyst relative to 100 parts by mass of the first catalyst is, for example, 5 to 240 parts by mass, preferably 40 to 240 parts by mass. Furthermore, the proportion of the second catalyst in catalyst layer 1 is, for example, 5% to 70% by mass, preferably 30% to 70% by mass. If the proportion of the second catalyst is within such a range, the hydrocarbon compound can be further stabilized for hydrocracking and / or isomerization.

[0086] The catalyst layer 1 having a single-layer structure can be prepared by any suitable method. Examples of methods for preparing the catalyst layer 1 having a single-layer structure include coating method, which forms the catalyst layer by coating a material containing a first catalyst and a second catalyst onto a ceramic substrate, and hydrothermal synthesis method.

[0087] The thickness of catalyst layer 1 with a single-layer structure is, for example, 1. m m~300 m m, preferably 2 m m~250 m m, more preferably 3 m m~200 m m, more preferably 5 m m~150 m m.

[0088] The catalyst layer 1, which has a single-layer structure, has an average pore size of, for example, 0.8 mm. m m~25 m m, preferably 1 m m~20 m m.

[0089] The porosity of the catalyst layer 1, which has a single-layer structure, is, for example, 30% to 80%, preferably 30% to 70%.

[0090] The thermal conductivity of the catalyst layer 1 having a single-layer structure is, for example, 0.01 W / m·K to 40 W / m·K, preferably 0.1 W / m·K to 40 W / m·K.

[0091] The weighted average thermal conductivity of the catalyst layer 1 having a single-layer structure and the thermal conductivity of the ceramic substrate 3 is, for example, 0.1 W / m·K or more, preferably 5 W / m·K or more, and more preferably 120 W / m·K or more. On the other hand, the upper limit of the weighted average thermal conductivity of the catalyst layer 1 having a single-layer structure and the thermal conductivity of the ceramic substrate 3 is typically 500 W / m·K.

[0092] If the weighted average of the thermal conductivity of the catalyst layer and the thermal conductivity of the ceramic substrate is within such a range, the temperature can be appropriately controlled throughout the entire catalyst layer, resulting in a further improvement in the selectivity of C5 to C20.

[0093] When the catalyst layer 1 has a stacked structure, the content of the first catalyst in the first catalyst layer 11 is, for example, 30% to 100% by mass, preferably 80% to 100% by mass. If the content of the first catalyst is in such a range, the above-mentioned hydrocarbon compound can be generated more stably from the feed gas.

[0094] When catalyst layer 1 has a stacked structure, the content of the second catalyst in the second catalyst layer 12 is, for example, 30% to 100% by mass, preferably 80% to 100% by mass. If the content of the second catalyst is in such a range, the hydrocarbon compound can be further stabilized for hydrocracking and / or isomerization.

[0095] The first catalyst layer 11 is prepared by any suitable method. Examples of methods for preparing the first catalyst layer 11 include coating method, which forms the catalyst layer by coating a material containing the first catalyst onto a ceramic substrate, and hydrothermal synthesis method.

[0096] The thickness of the first catalyst layer 11 is, for example, 3. m m~200 m m, preferably 5 m m~150 m m.

[0097] The average pore size of the first catalyst layer 11 is, for example, 0.8 mm. m m~25 m m, preferably 1 m m~20 m m.

[0098] The porosity of the first catalyst layer 11 is, for example, 30% to 80%, preferably 30% to 70%.

[0099] The thermal conductivity of the first catalyst layer 11 is, for example, 0.01 W / m·K to 40 W / m·K, preferably 0.1 W / m·K to 40 W / m·K.

[0100] The weighted average thermal conductivity of the first catalyst layer 11 and the thermal conductivity of the ceramic substrate 3 is, for example, 0.1 W / m·K or more, preferably 5 W / m·K or more, and more preferably 120 W / m·K or more. On the other hand, the upper limit of the weighted average thermal conductivity of the first catalyst layer 11 and the thermal conductivity of the ceramic substrate 3 is typically 500 W / m·K.

[0101] If the weighted average of the thermal conductivity of the first catalyst layer and the thermal conductivity of the ceramic substrate is within such a range, the temperature can be appropriately controlled throughout the entire first catalyst layer, resulting in a further improvement in the selectivity of C5 to C20.

[0102] The second catalyst layer 12 is prepared by any suitable method. Examples of methods for preparing the second catalyst layer include coating methods, which form the second catalyst layer by coating a material containing the second catalyst onto a ceramic substrate, and reaction methods, such as hydrothermal synthesis, which form the second catalyst layer.

[0103] When the second catalyst layer 12 is prepared by coating, the average pore size in the second catalyst layer 12 is, for example, 0.8 mm. m m~25 m m, preferably 1 m m~20 m m. Furthermore, the porosity of the second catalyst layer 12 is, for example, 30% to 80%, preferably 30% to 70%. Additionally, the thickness of the second catalyst layer 12 is, for example, 3 m. m m~200 m m, preferably 5 m m~100 m m.

[0104] On the other hand, if the second catalyst layer 12 is prepared by a reaction method, the second catalyst layer 12 is configured as a denser thin film than that prepared by coating. The thickness of the second catalyst layer 12 is, for example, 1... m m~80 m m, preferably 2 m m~50 m m.

[0105] The thermal conductivity of the second catalyst layer 12 is, for example, 0.01 W / m·K to 40 W / m·K, preferably 0.1 W / m·K to 40 W / m·K.

[0106] The weighted average thermal conductivity of the second catalyst layer 12 and the thermal conductivity of the ceramic substrate 3 is, for example, 0.1 W / m·K or more, preferably 5 W / m·K or more, and more preferably 120 W / m·K or more. On the other hand, the upper limit of the weighted average thermal conductivity of the second catalyst layer 12 and the thermal conductivity of the ceramic substrate 3 is typically 500 W / m·K.

[0107] If the weighted average of the thermal conductivity of the second catalyst layer and the thermal conductivity of the ceramic substrate is within such a range, the temperature can be appropriately controlled throughout the second catalyst layer, resulting in a further improvement in the selectivity of C5 to C20.

[0108] Such catalyst layer 1 (first catalyst layer 11 and second catalyst layer 12 each) may further contain additive materials.

[0109] Examples of additives include fillers, binders, sintering inhibitors, and catalysts. Additives can be used alone or in combination.

[0110] The proportion of the added material relative to 100 parts by mass of the first catalyst is, for example, 0 to 70 parts by mass, preferably 0 to 40 parts by mass.

[0111] Among the added materials, fillers are preferred.

[0112] Examples of fillers include Al2O3, AlN, BN, BeO, SiC, Si, Al, Au, Cu, Ag, Si3N4, SiO2, ZnO, MgO, and carbon, with Al2O3, AlN, and BN being preferred. The fillers can be used alone or in combination.

[0113] The thermal conductivity of the filler is, for example, 0.1 W / m·K to 500 W / m·K, preferably 5 W / m·K to 500 W / m·K. If the catalyst layer contains a filler with such thermal conductivity, the thermal conductivity of the catalyst layer can be stably adjusted within the above range.

[0114] The average particle size (average maximum length) of the filler is, for example, 5 nm or more, preferably 10 nm or more, and more preferably 50 nm or more. On the other hand, the average particle size of the filler is, for example, 1000 nm or less, preferably 500 nm or less.

[0115] The length-to-diameter ratio of the packing is, for example, 1.2 or more, preferably 1.5 or more. On the other hand, the length-to-diameter ratio of the packing is, for example, 500 or less, preferably 300 or less.

[0116] B-2. Details of the fuel manufacturing unit 101 like Figure 4 and Figure 5 As shown, the fuel manufacturing apparatus 101 has a flow-through structure.

[0117] In one embodiment, the fuel manufacturing apparatus 101 includes a honeycomb substrate 3b as a ceramic substrate 3. The honeycomb substrate 3b has partitions 31 defining a plurality of pores 32. At least a portion of the plurality of pores 32 includes a gas flow path 4. In the example shown, all of the plurality of pores 32 include a gas flow path 4. A catalyst layer 1 is disposed on the surface of the partitions 31.

[0118] If the fuel manufacturing device has such a configuration, it can fully ensure the contact area between the raw material gas and the catalyst layer, thereby improving the efficiency of synthetic fuel manufacturing.

[0119] The honeycomb substrate 3b has any suitable shape (overall shape). Examples of honeycomb substrate shapes include a cylindrical shape with a circular base, an elliptical cylindrical shape with an elliptical base, a prism shape with a polygonal base, and a column shape with an irregular base. In one embodiment, the honeycomb substrate 3b has a cylindrical shape. The outer diameter and length of the honeycomb substrate 3b can be appropriately set according to the purpose.

[0120] The pore density in the honeycomb substrate 3b is, for example, 150 cpsi or more, preferably 200 cpsi or more, and more preferably 300 cpsi or more. On the other hand, the pore density in the honeycomb substrate 3b is, for example, 1200 cpsi or less, preferably 900 cpsi or less.

[0121] It should be noted that in this specification, "cell density of a honeycomb structure" refers to the cell density of a cross-section along the length of the honeycomb structure (the direction in which the cells extend), and "cpsi" refers to 6.4516 cm⁻¹ of that cross-section. 2 The total number of holes in a 1 square inch.

[0122] In the example shown, the honeycomb substrate 3b has an outer wall 33 and a partition wall 31. The outer wall 33 and the partition wall 31 can be formed integrally or separately. In the example shown, the outer wall 33 and the partition wall 31 are formed integrally.

[0123] The outer wall 33 has a cylindrical shape. The thickness of the outer wall 33 can be appropriately set according to the application of the fuel manufacturing device. The thickness of the outer wall 33 is, for example, 0.1 mm to 10 mm, or, for example, 0.2 mm to 8 mm, or, for example, 1 mm to 5 mm.

[0124] Partition 31 is located inside outer wall 33. In the example shown, partition 31 has a first partition 31a and a second partition 31b that are orthogonal to each other, and the first partition 31a and the second partition 31b define a plurality of holes 32. Examples of cross-sectional shapes for the holes 32 include triangles, quadrilaterals, pentagons, polygons of more than one hexagon, circles, and ellipses. In the example shown, the cross-sectional shape of each of the plurality of holes 32 is quadrilateral except for the portions where the first partition 31a and the second partition 31b are in contact with outer wall 33. It should be noted that the structure of the partition is not limited to the partition 31 described above. The partition may also have a first partition extending in a radial direction and a second partition extending in a circumferential direction, which define a plurality of holes.

[0125] The perforated grid 32 will be described in the same manner as the cylindrical substrate 3a described above.

[0126] Typically, multiple perforations 32 extend from the first end face E1 (inflow end face) of the fuel manufacturing device to the second end face E2 (outflow end face) along the length direction (axial direction) of the fuel manufacturing device.

[0127] In the example shown, the catalyst layer 1 described above is stacked on the inner surface of the perforated grid 32. A gas flow path 4 is formed in the portion of the cross-section of the perforated grid 32 where the catalyst layer 1 is not formed (typically the central portion). The gas flow path 4 extends from the first end face E1 (inflow end face) of the fuel production device to the second end face E2 (outflow end face). The gas flow path 4 has any suitable shape in a cross-section orthogonal to the length direction. Examples of cross-sectional shapes for the gas flow path 4 include those similar to the perforated grid 32 described above.

[0128] The partition 31 can be configured to allow synthetic fuel gas to pass through substantially, or it can be configured to prevent synthetic fuel gas from passing through substantially.

[0129] The thickness of the partition wall 31 is, for example, 0.0508 mm or more, preferably 0.0635 mm or more, and more preferably 0.203 mm or more. On the other hand, the thickness of the partition wall 31 is, for example, 1.52 mm or less, preferably 1.27 mm or less, and more preferably 0.305 mm or less.

[0130] The porosity of the partition wall 31 is, for example, 80% or less, preferably 65% ​​or less, and more preferably 10% or less. On the other hand, the lower limit of the porosity of the partition wall 31 is typically 0%.

[0131] If the thickness and / or porosity of the partition wall are within such a range, the thermal conductivity of the partition wall can be stably adjusted to the range of thermal conductivity of the ceramic substrate described above.

[0132] When the partition wall 31 has pores, the average pore diameter of the partition wall 31 is, for example, 5. m m~30 m m, preferably 8 m m~25 m m.

[0133] B-3. ​​Details of the fuel production unit 102 like Figure 6 As shown, the fuel manufacturing apparatus 102 may also have a wall-flow structure. In this case, the fuel manufacturing apparatus 102 has a second gas flow path 5 in addition to the gas flow path 4 (hereinafter sometimes referred to as the first gas flow path 4).

[0134] The second gas flow path 5 is located on the opposite side of the gas flow path 4 relative to the catalyst layer 1. The synthetic fuels generated through the hydrocracking and / or isomerization reactions of the aforementioned hydrocarbon compounds typically flow into the second gas flow path 5 in a gaseous state. Therefore, the synthetic fuels can be successfully recovered from the second gas flow path.

[0135] In one embodiment, the fuel manufacturing apparatus 102 includes a honeycomb substrate 3b and a catalyst layer 1. In the fuel manufacturing apparatus 102, the partitions 31 of the honeycomb substrate 3b define a plurality of first pores 321 and a plurality of second pores 322.

[0136] The first hole 321 and the second hole 322 are described in the same way as the hole 32 described above.

[0137] At least a portion of the plurality of first apertures 321 includes the first gas flow path 4 described above. In the example shown in the figure, all of the plurality of first apertures 321 include the first gas flow path 4 described above.

[0138] Furthermore, at least a portion of the plurality of second apertures 322 includes the aforementioned second gas flow path 5. In the example shown in the figure, all of the plurality of second apertures 322 include the aforementioned second gas flow path 5.

[0139] The second gas flow path 5 is a space formed inside the second aperture 322. In the example shown, the second gas flow path 5 is defined by the inner surface of the second aperture 322.

[0140] The second gas flow path 5 has any suitable shape in its cross-section in a direction orthogonal to the length direction. For example, the same cross-sectional shape as the gas flow path 4 described above can be used as the cross-sectional shape of the second gas flow path 5.

[0141] The cross-sectional area of ​​the second gas flow path 5 can be the same as or different from the cross-sectional area of ​​the gas flow path 4.

[0142] In this embodiment, the first aperture 321 and the second aperture 322 are connected to each other by a shared partition 31. The partition 31 is configured to allow synthetic fuel (typically synthetic fuel gas) to pass through. Therefore, the fluid flowing in the fuel manufacturing apparatus 102 flows from the gas flow path 4 through the partition 31 into the second gas flow path 5.

[0143] In this case, the average pore size of the partition wall 31 is, for example, 5. m m~30 m m, preferably 8 m m~25 m m. In addition, the porosity of the partition wall 31 is, for example, 20% to 75%, preferably 25% to 70%.

[0144] Within the partition wall, if the average pore size and / or porosity are within such a range, then the synthetic fuel gas can be stably permeated.

[0145] like Figure 7 As shown, the fuel manufacturing apparatus 102 may also include a first sealing part 6 and / or a second sealing part 7.

[0146] The first sealing part 6 and the second sealing part 7 are respectively configured to be substantially impermeable to the raw material gas.

[0147] The first sealing part 6 is provided on at least a portion of the plurality of first holes 321. In the example shown in the figure, the first sealing part 6 is provided on all of the plurality of first holes 321. The first sealing part 6 seals the end of the gas flow path 4 on the second end face E2 (outflow end face) side.

[0148] The first sealing part 6 can be made of any suitable material. For example, the ceramic material described above can be used as a component material of the first sealing part 6. The component materials of the first sealing part 6 can be used alone or in combination.

[0149] In the example shown, the first sealing part 6 is fixed to the partition wall 31. The first sealing part 6 and the partition wall 31 can be formed integrally or separately. In one embodiment, the first sealing part 6 and the partition wall 31 are formed integrally.

[0150] The size of the first sealing portion 6 in the direction in which the first aperture 321 extends is typically larger than the thickness of the partition wall 31. The size of the first sealing portion 6 in the direction in which the first aperture 321 extends is, for example, more than twice, preferably more than three times, the thickness of the partition wall 31. If the first sealing portion has such a size, the permeation of the raw material gas can be sufficiently suppressed.

[0151] On the other hand, the size of the first sealing portion 6 in the direction in which the first hole 321 extends is, for example, less than 180 times, preferably less than 160 times, relative to the thickness of the partition wall 31.

[0152] The second sealing part 7 is provided on at least a portion of the plurality of second holes 322. In the example shown, the second sealing part 7 is provided on all of the plurality of second holes 322. The second sealing part 7 seals the end of the second gas flow path 5 on the first end face E1 (inflow end face) side.

[0153] The second sealing part 7 can be made of any suitable material. For example, the same material as the first sealing part 6 described above can be used as a component of the second sealing part 7. The component materials of the second sealing part 7 can be used alone or in combination.

[0154] In the example shown, the second sealing part 7 is fixed to the partition wall 31. The second sealing part 7 can be integrally formed with the partition wall 31 or it can be separately formed from the partition wall 31. In one embodiment, the second sealing part 7 is integrally formed with the partition wall 31.

[0155] The size of the second sealing portion 7 in the direction in which the second aperture 322 extends is typically larger than the thickness of the partition wall 31. The range of the size of the second sealing portion 7 in the direction in which the second aperture 322 extends is, for example, the same as the range of the size of the first sealing portion 6 described above. If the second sealing portion has such a size, the permeation of the raw material gas can be sufficiently suppressed.

[0156] B-4. Variation Example In the aforementioned fuel manufacturing apparatuses 100, 101, and 102, the catalyst layer 1 may contain a third catalyst, in addition to the first and second catalysts, capable of promoting a reverse conversion reaction that converts carbon dioxide into carbon monoxide. The third catalyst may be dispersed in the catalyst layer 1 having a monolayer structure, or the catalyst layer 1 having a stacked structure may contain a third catalyst layer containing the third catalyst.

[0157] In this case, a feed gas containing carbon dioxide and hydrogen is supplied to gas flow path 4. Then, the reverse conversion reaction shown in equation (2) is successfully carried out by the third catalyst to produce carbon monoxide.

[0158] CO2 + H2 → CO + H2O ···(2) Then, the FT reaction shown in equation (1) above is carried out using a first catalyst. Therefore, synthetic fuel gas can be efficiently produced from a feedstock gas containing carbon dioxide.

[0159] The third catalyst contains any suitable active ingredient. Examples of active ingredients for the third catalyst include Ni, Cu, Mo, Fe, Pt, Rh, Co, Zn, and Ba. The active ingredients of the third catalyst can be used alone or in combination.

[0160] The third catalyst may contain these elements in a metallic state (e.g., pure metal, alloy) or in a compound state (e.g., oxide, carbide).

[0161] In addition to the active components mentioned above, the third catalyst may also contain a support. Examples of supports for the third catalyst include those similar to those used for the first catalyst.

[0162] C. Methods for manufacturing synthetic fuels Next, for convenience, refer to Figure 5 The fuel manufacturing apparatus 101 shown illustrates a method for manufacturing synthetic fuel according to one embodiment.

[0163] In one embodiment, the fuel manufacturing apparatus 101 is heated to a predetermined FT reaction start temperature. The FT reaction start temperature is, for example, 200°C to 400°C.

[0164] Next, the raw material gas containing carbon monoxide and hydrogen is supplied to the gas flow path 4 of the fuel manufacturing device 101.

[0165] The carbon monoxide content in the feed gas is, for example, 25% to 50% by volume, preferably 28% to 40% by volume.

[0166] The hydrogen content in the feed gas is, for example, 50% to 75% by volume, preferably 60% to 72% by volume.

[0167] In addition, the pressure of the gas flow path 4 is, for example, 0.7 MPa (absolute pressure) to 4.0 MPa (absolute pressure), preferably 0.8 MPa (absolute pressure) to 3.5 MPa (absolute pressure).

[0168] Thus, the feed gas comes into contact with the catalyst layer at the FT reaction initiation temperature, starting the FT reaction as described in equation (1) above. This typically produces a hydrocarbon compound containing n-chain alkanes. The hydrocarbon compound may further contain iso-chain alkanes.

[0169] In hydrocarbon compounds, the number of carbon atoms in a normal-chain alkane is, for example, 1 to 100, and the number of carbon atoms in an iso-chain alkane is, for example, 4 to 20.

[0170] In addition, when the catalyst layer 1 contains a first catalyst comprising transition metals and alkali metals, or when the catalyst layer 1 contains a third catalyst and a first catalyst without alkali metals, a feed gas containing carbon dioxide and hydrogen is supplied to the gas flow path 4 of the fuel manufacturing apparatus 101.

[0171] In this case, the carbon dioxide content in the feed gas is, for example, 20% to 40% by volume, preferably 22% to 29% by volume.

[0172] In addition, the hydrogen content in the feed gas is, for example, 60% to 80% by volume, preferably 71% to 78% by volume.

[0173] Thus, the feed gas comes into contact with catalyst layer 1, initiating the reverse conversion reaction of equation (2) and the Fourier transform reaction of equation (1) in sequence. As a result, a hydrocarbon compound containing n-chain alkanes is generated.

[0174] The proportion of n-chain alkanes in the hydrocarbon compound is, for example, 30% to 100% by volume. The proportion of iso-chain alkanes in the hydrocarbon compound is, for example, 0% to 15% by volume, preferably 0% to 10% by volume.

[0175] In addition, hydrocarbon compounds may further contain olefins (olefins). In hydrocarbon compounds, the number of carbon atoms in olefins is, for example, 3 to 10.

[0176] The proportion of olefins in the hydrocarbon compound is, for example, 0% to 70% by volume, preferably 0% to 60% by volume.

[0177] At least a portion of such hydrocarbon compounds (representatively n-alkanes) are hydrocracking and / or isomerized to convert them into liquid fuel components with 5 to 20 carbon atoms. Examples of liquid fuel components include n-alkanes with 5 to 20 carbon atoms, iso-alkanes (branched alkanes) with 5 to 20 carbon atoms, and alkenes with 5 to 20 carbon atoms. The liquid fuel components are in a liquid state at ambient temperature and pressure (23°C, 0.1 MPa). Furthermore, the conversion of hydrocarbon compounds to methane is suppressed in the fuel production apparatus.

[0178] This results in the production of synthetic fuels containing 5 to 20 carbon atoms, which are fully incorporated into liquid fuel components.

[0179] The methane content in the synthetic fuel gas is, for example, 20% by volume or less, preferably 15% by volume or less, more preferably 13% by volume or less, and even more preferably 12% by volume or less. On the other hand, the lower limit of the methane content in the synthetic fuel gas is typically 0% by volume.

[0180] The proportion of hydrocarbons with 2 to 4 carbon atoms in the synthetic fuel gas is, for example, 12% by volume or less, preferably 10% by volume or less, more preferably 8% by volume or less, and even more preferably 7% by volume or less. On the other hand, the proportion of hydrocarbons with 2 to 4 carbon atoms in the synthetic fuel gas is, for example, 0% by volume or more, and also, for example, 5% by volume or more.

[0181] The proportion of liquid fuel components with 5 to 20 carbon atoms in the synthetic fuel gas is, for example, 45% by volume or more, preferably 50% by volume or more, more preferably 55% by volume or more, even more preferably 60% by volume or more, and particularly preferably 65% ​​by volume or more. On the other hand, the proportion of liquid fuel components with 5 to 20 carbon atoms in the synthetic fuel gas is, for example, 100% by volume or less, and also, for example, less than 85% by volume, and also, for example, 80% by volume or less.

[0182] The proportion of hydrocarbons with more than 20 carbon atoms in the synthetic fuel gas is, for example, 25% by volume or less, preferably 20% by volume or less, and more preferably 16% by volume or less. On the other hand, the proportion of hydrocarbons with more than 20 carbon atoms in the synthetic fuel gas is, for example, 0% by volume or more, and also, for example, 5% by volume or more.

[0183] Such synthetic fuels, because they contain liquid fuel components with 5 to 20 carbon atoms, are suitable as alternative fuels to petroleum.

[0184] The fuel manufacturing apparatus can achieve a C5 to C20 selectivity of 45% or more, preferably 50% or more, more preferably 55% or more, even more preferably 60% or more, and particularly preferably 65% ​​or more. On the other hand, the upper limit of the C5 to C20 selectivity is 100%.

[0185] Example The present invention will be specifically described below through embodiments, but the present invention is not limited to these embodiments.

[0186] <Example 1> <<Preparation of honeycomb substrate>> A honeycomb dried body is prepared by extruding and drying a blank containing SiC powder. The honeycomb dried body has a cylindrical shape with a diameter of 20 mm and a length of 50 mm.

[0187] The honeycomb dryer has partitions with a defined number of cells and an outer wall surrounding the partitions. The cross-sectional shape of the cells is quadrilateral. The cell density in the honeycomb dryer is 300 cpsi, and the thickness of the partitions is 0.254 mm.

[0188] In addition, the material containing Si powder is pressed into shape and then dried to obtain a Si donor.

[0189] Next, with the Si supply in contact with the honeycomb drying body, the mixture is heated at 1500°C for 4 hours under reduced pressure (200 Pa) to impregnate the honeycomb drying body with molten metal containing Si.

[0190] Therefore, a honeycomb substrate composed of a dense Si-SiC composite material was prepared. The septa of this honeycomb substrate are pore-free, that is, the porosity of the septa of the honeycomb substrate is 0%. The thermal conductivity of the honeycomb substrate is shown in Table 1.

[0191] <<Preparation of the First Catalyst>> Silica (IV) particles were introduced into distilled water and stirred for 12 hours under reduced pressure at room temperature (23°C). This yielded a dispersion of metal oxide particles. Meanwhile, cobalt (II) hexahydrate was dissolved in distilled water to obtain an aqueous cobalt nitrate solution. Next, the aqueous cobalt nitrate solution was added to the metal oxide particle dispersion, and the mixture was stirred for 2 hours at room temperature (23°C). Then, the mixture of dispersion and aqueous solution was heated to 80°C while stirring to evaporate the water. The remaining solids were then heated at 500°C for 3 hours. This yielded FT reaction catalyst particles (hereinafter referred to as catalyst particles) serving as the first catalyst. The catalyst particles comprise cobalt tetroxide (Co3O4) and cobalt tetroxide (Co3O4) supported silica (IV). In the FT reaction catalyst particles, the Co content is 20 parts by mass relative to 100 parts by mass of silica. Hereinafter, the first catalyst comprising cobalt tetroxide and silica is sometimes referred to as the first catalyst (Co / SiO2).

[0192] <<Preparation of the Second Catalyst>> The commercially available HZSM-5 (zeolite, manufactured by Nakamura Superhard Co., Ltd.) was calcined in an electric furnace at 500°C for 4 hours to obtain the second catalyst.

[0193] <<Preparation of Catalyst Layer>> A catalyst slurry was prepared by dispersing the particles of the first and second catalysts in distilled water at the same mass. The catalyst particles in the slurry comprised 10% by mass. Next, the honeycomb substrate prepared above was immersed in the catalyst slurry for 5 seconds at atmospheric pressure (0.1 MPa) and room temperature (23°C). Then, the honeycomb substrate was pulled out of the catalyst slurry. This coated the surface of the partition wall with the catalyst slurry. The catalyst slurry coated on the surface of the partition wall was then dried by heating at 100°C for 120 minutes. This immersion and drying process was repeated to form a catalyst layer with a monolayer structure on the surface of the partition wall. The catalyst layer contained aggregates of catalyst particles. The thickness of the catalyst layer was 230 mm. m m. The catalyst particle loading per unit area of ​​the partition wall is 0.023 g / cm². 2 .

[0194] Through the above, a fuel manufacturing apparatus with a honeycomb substrate and a catalyst layer was manufactured.

[0195] <Example 2> The honeycomb substrate, which is composed of a dense body of Si-SiC composite material, is replaced with the honeycomb substrate prepared below. Otherwise, the fuel manufacturing apparatus is manufactured in the same manner as in Example 1.

[0196] A blank containing 80 parts by weight of SiC raw material powder and 20 parts by weight of metallic Si powder was extruded and dried. It was then calcined at 550°C for 3 hours in an oxidizing atmosphere, followed by calcination at 1450°C for 2 hours in a non-oxidizing atmosphere. This yielded a honeycomb substrate. The honeycomb substrate had the same dimensions and structure as the dried honeycomb body of Example 1. The honeycomb substrate was composed of a porous Si-SiC composite material. The thickness of the partition walls in the honeycomb substrate was 0.254 mm, and the average pore size of the partition walls was 28 mm. m m, the porosity of the adjacent wall is 63%.

[0197] <Example 3> The clay containing SiC raw material powder and metallic Si powder was replaced with clay containing cordierite (Cd), and the fuel manufacturing apparatus was manufactured in the same manner as in Example 1. In the fuel manufacturing apparatus of Example 3, the average pore size of the partition wall was 11. m m, the porosity of the adjacent wall is 52%.

[0198] <Comparative Example 1> The first and second catalysts, prepared in the same manner as in Example 1, were respectively pressurized, shaped, and pulverized to form granular bodies (containing catalyst particles) with an aggregate diameter of 0.5~1.5 mm. The particles of the first and second catalysts were mixed at a mass ratio of 1:1, and quartz wool was laid on the top and bottom of the reaction tube, with an equal amount of the same filling material as in Example 1.

[0199] Through the above operations, a fuel manufacturing apparatus is manufactured in which a gas flow path is filled with catalyst particles.

[0200] <Example 4> The first catalyst (Co / SiO2) was replaced with the first catalyst (K-Co / SiO2) prepared below, and the fuel manufacturing apparatus was otherwise manufactured in the same manner as in Example 1.

[0201] Silica (IV) particles were introduced into distilled water and stirred under reduced pressure at room temperature (23°C) for 12 hours. This yielded a dispersion of metal oxide particles. Separately, cobalt (II) hexahydrate and potassium nitrate were dissolved in distilled water to obtain an aqueous solution of cobalt nitrate and potassium nitrate.

[0202] Next, the aqueous solution was added to the dispersion of metal oxide particles, and the mixture was stirred at room temperature (23°C) for 2 hours. Then, the mixture of dispersion and aqueous solution was heated to 80°C while stirring to evaporate the water. The remaining solids were then heated at 500°C for 3 hours. This yielded catalyst particles used as the first catalyst. The catalyst particles contained potassium nitrate, cobalt tetroxide (Co3O4), and silica (IV) supporting them. The content of Co in the catalyst particles was 15% by mass, and the content of K was 1% by mass.

[0203] <Example 5> SiO2 particles were further added to the catalyst slurry as filler, and the fuel manufacturing apparatus was otherwise manufactured in the same manner as in Example 4.

[0204] The addition rate of SiO2 particles in the catalyst slurry is 20 parts by mass relative to 100 parts by mass of the first catalyst.

[0205] In addition, the thermal conductivity of SiO2 particles is 1.38 W / m·K, the average particle size of SiO2 particles is 20 nm, and the aspect ratio of SiO2 particles is 1.0.

[0206] <Example 6> Further addition to the catalyst slurry α Al2O3 particles were used as fillers, and the fuel manufacturing apparatus was otherwise manufactured in the same manner as in Example 1.

[0207] In catalyst slurry α The addition rate of Al2O3 particles is 20 parts by mass relative to 100 parts by mass of the first catalyst.

[0208] in addition, α The thermal conductivity of Al2O3 particles is 30 W / m·K. α The average particle size of Al2O3 particles is 400 nm. α -The aspect ratio of Al2O3 particles is 10.

[0209] <Example 7> The first catalyst (Co / SiO2) was changed to the first catalyst (K-Co / SiO2) prepared in Example 4, and the fuel manufacturing apparatus was otherwise manufactured in the same manner as in Example 2.

[0210] <Example 8> The first catalyst (Co / SiO2) was changed to the first catalyst (K-Co / SiO2) prepared in Example 4, and the fuel manufacturing apparatus was otherwise manufactured in the same manner as in Example 3.

[0211] <Example 9> The fuel manufacturing apparatus was otherwise manufactured in the same manner as in Example 1, except that the first catalyst (Co / SiO2) was replaced with the first catalyst (Na-Fe3O4) prepared below.

[0212] First, iron(III) oxide (Fe3O4) particles are synthesized by any suitable method.

[0213] Then, the synthesized iron(III) oxide (Fe3O4) particles were introduced into distilled water and stirred under reduced pressure at room temperature (23°C) for 12 hours. This yielded a dispersion of iron(III) oxide. Separately, sodium nitrate was dissolved in distilled water to obtain an aqueous solution of sodium nitrate.

[0214] Next, an aqueous solution of sodium nitrate was added to the iron(III) oxide dispersion, and the mixture was stirred at room temperature (23°C) for 2 hours. Then, the mixture of dispersion and aqueous solution was heated to 80°C while stirring to evaporate the water. The remaining solids were then heated at 500°C for 3 hours. This yielded catalyst particles, which served as the first catalyst. The catalyst particles contained sodium nitrate and iron(III) oxide (Fe3O4). The Na content in the catalyst particles was 1% by mass.

[0215] <Example 10> Nickel oxide (NiO) and zinc oxide (ZnO) were further added to the catalyst slurry as a third catalyst, and the fuel manufacturing apparatus was otherwise manufactured in the same manner as in Example 1.

[0216] The amount of nickel oxide added is 50 parts by mass relative to 100 parts by mass of the first catalyst, and the amount of zinc oxide added is 50 parts by mass relative to 100 parts by mass of the first catalyst.

[0217] <Example 11> <<Preparation of honeycomb substrate>> The honeycomb substrate was prepared in the same manner as in Example 1.

[0218] <<Preparation of the Second Catalyst Layer>> Commercially available HZSM-5 (zeolite, manufactured by Nakamura Superhard Co., Ltd.) was calcined in an electric furnace at 500°C for 4 hours to obtain second catalyst particles.

[0219] The obtained second catalyst particles were dispersed in distilled water to prepare a second catalyst slurry. The catalyst particles in the second catalyst slurry accounted for 10% by mass. Next, the honeycomb substrate prepared above was immersed in the second catalyst slurry for 5 seconds at atmospheric pressure (0.1 MPa) and room temperature (23°C). Then, the honeycomb substrate was pulled out of the second catalyst slurry. As a result, the second catalyst slurry was coated on the surface of the partition wall. Then, the second catalyst slurry coated on the surface of the partition wall was heated at 100°C for 120 minutes to dry it. The above immersion and drying were repeated to form a second catalyst layer on the surface of the partition wall. The thickness of the second catalyst layer was 150 mm. m m. The loading of the second catalyst particles per unit area of ​​the partition wall is 0.13 g / cm³. 2 .

[0220] <<Preparation of the First Catalyst Layer>> The first catalyst (K-Co / SiO2) was prepared in the same manner as in Example 4. The obtained first catalyst (K-Co / SiO2) was dispersed in distilled water to prepare a first catalyst slurry. The catalyst particles in the first catalyst slurry comprised 10% by mass. Next, a honeycomb substrate with a second catalyst layer formed thereon was immersed in the first catalyst slurry for 5 seconds at atmospheric pressure (0.1 MPa) and room temperature (23°C). Then, the honeycomb substrate was pulled out of the first catalyst slurry. This resulted in the first catalyst slurry being coated onto the surface of the second catalyst layer. The first catalyst slurry coated onto the surface of the second catalyst layer was then heated at 100°C for 120 minutes to dry it. This immersion and drying process was repeated to form a first catalyst layer on the surface of the second catalyst layer. The thickness of the first catalyst layer was 150 mm. m m. The loading of the first catalyst particles per unit area of ​​the partition wall is 0.13 g / cm³. 2 .

[0221] Through the above operations, a fuel manufacturing apparatus with a catalyst layer having a layered structure is manufactured.

[0222] <Comparative Example 2> The first catalyst (K-Co / SiO2) prepared in the same manner as in Example 4 and the second catalyst (HZSM-5) prepared in the same manner as in Example 1 were respectively pressurized, molded, and pulverized to form granular molded bodies (containing catalyst particles) with an aggregate diameter of 0.5~1.5 mm. The particles of the first catalyst and the second catalyst were mixed in a mass ratio of 1:1, and the mixture was placed on the top and bottom of the reaction tube with quartz wool, with the same amount of wool filling the space between them as in Example 4.

[0223] Through the above operations, a fuel manufacturing apparatus is manufactured in which a gas flow path is filled with catalyst particles.

[0224] <Experimental Study in the Production of Synthetic Fuels> <<Synthetic Fuels Made from CO>> Four thermocouples were installed in the gas flow path of the fuel manufacturing apparatus obtained in Examples 1-3 and Comparative Example 1. More specifically, thermocouples were installed in the gas flow path at positions of 5 mm, 20 mm, 32 mm, and 45 mm from the end face on the inflow side.

[0225] Next, the fuel manufacturing apparatus was inserted into a reaction tube with an inner diameter of 21 mm. As a pretreatment for the reaction, the fuel manufacturing apparatus was heated to 240°C using an electric furnace located around the outer periphery of the reaction tube, and hydrogen gas was introduced into the reaction tube to reduce the first catalyst. Then, nitrogen gas was passed through the reaction tube to lower the temperature of the electric furnace to 200°C, and a feed gas containing 33 mol% carbon monoxide and 66 mol% hydrogen was introduced at a space velocity SV = 1018 h⁻¹. -1 Import into the reaction tube.

[0226] Therefore, feedstock gas is supplied to the gas flow path of the fuel manufacturing device, and the synthesized fuel gas flows out from the reaction tube. The internal pressure of the gas flow path is 1 MPa. At this time, the temperature at each location in the gas flow path is measured using the four thermocouples mentioned above. The highest and lowest temperatures in the gas flow path and their temperature differences are shown in Table 1.

[0227] In addition, the composition of the synthetic fuel gas flowing out of the reaction tube after the heating of the electric furnace was stopped was determined using gas chromatography-thermal conductivity detector (GC-TCD).

[0228] <<Synthetic Fuels Made from CO2>> The fuel manufacturing apparatus obtained in Examples 4-11 and Comparative Example 2 was inserted into a reaction tube with an inner diameter of 21 mm. As a pretreatment for the reaction, the fuel manufacturing apparatus was heated to 350°C using an electric furnace located around the outer periphery of the reaction tube, and hydrogen gas was introduced into the reaction tube to reduce the first catalyst. Next, nitrogen gas was passed through the reaction tube to adjust the temperature of the electric furnace to 300°C, and a feed gas containing 25 mol% carbon dioxide and 75 mol% hydrogen was introduced at a space velocity SV 1018 h. -1 Import into the reaction tube.

[0229] Therefore, feedstock gas is supplied to the gas flow path of the fuel manufacturing unit, and the synthesized fuel gas flows out from the reaction tube. The internal pressure of the gas flow path is 1 MPa.

[0230] In addition, the composition of the synthetic fuel gas flowing out of the reaction tube after the heating of the electric furnace was stopped was determined using gas chromatography-thermal conductivity detector (GC-TCD).

[0231] Based on the above GC-TCD measurement results, the conversion rate (%) from carbon monoxide to hydrocarbon compounds was calculated using the following formula (A-1).

[0232] CO conversion rate (%) = (Amount of hydrocarbons in the synthetic fuel gas (volume%) / Total amount of hydrocarbons and carbon monoxide in the synthetic fuel gas (volume%)) × 100··· (A-1) In addition, the conversion rate (%) from carbon dioxide to hydrocarbon compounds is calculated using the following formula (A-2).

[0233] CO2 conversion rate (%) = (Amount of hydrocarbon compounds in the synthetic fuel gas (volume%) / Total amount of hydrocarbon compounds and carbon dioxide in the synthetic fuel gas (volume%)) × 100··· (A-2) In addition, the CH4 selectivity (%) is calculated using the following formula (B).

[0234] CH4 selectivity (%) = (Amount of methane in the synthetic fuel gas (volume %) / Total amount of hydrocarbon compounds and carbon oxides in the synthetic fuel gas (volume %)) × 100 ··· (B) In addition, the selection rates (%) of C2 to C4 are calculated using the following formula (C).

[0235] C2~C4 selectivity (%) = (Total C2~C4 hydrocarbons in the synthetic fuel gas (volume %) / Total amount of hydrocarbons and carbon oxides in the synthetic fuel gas (volume %)) × 100··· (C) In addition, the selection rate (%) of C5 to C20 is calculated using the following formula (D).

[0236] C5~C20 selectivity (%) = (Total C5~C20 hydrocarbons in the synthetic fuel gas (volume %) / Total amount of hydrocarbons and carbon oxides in the synthetic fuel gas (volume %)) × 100··· (D) Then, the C20+ selection rate (%) is calculated using the following formula (E).

[0237] C20+ selectivity (%) = (total amount of hydrocarbons exceeding C20 in the synthetic fuel gas (volume %) / total amount of hydrocarbons and carbon oxides in the synthetic fuel gas (volume %)) × 100··· (E) These results are shown in Tables 1 and 2.

[0238] [Table 1]

[0239] [Table 2]

[0240] <Evaluation> As shown in Table 1, if the catalyst layer containing the first catalyst and the second catalyst is disposed on the surface of the ceramic substrate in a manner facing the gas flow path, the selectivity and yield of C5 to C20 can be significantly improved compared with the case where the gas flow path is filled with catalyst particles.

[0241] Industrial applicability The fuel manufacturing apparatus described in the embodiments of the present invention can be used for the manufacture of synthetic fuels, and is particularly preferred for the manufacture of petroleum alternative fuels that contain liquid fuel components with 5 to 20 carbon atoms.

[0242] Explanation of reference numerals in the attached figures 1. Catalyst layer 11 First catalyst layer 12 Second catalyst layer 3 Ceramic substrate 4 Gas Flow Path 100 Fuel Manufacturing Unit 101 Fuel Manufacturing Unit 102 Fuel manufacturing unit.

Claims

1. A fuel manufacturing apparatus, characterized in that, have: A ceramic substrate, wherein a gas flow path is specified for supplying a raw material gas containing carbon oxides and hydrogen; and A catalyst layer is disposed on the surface of the ceramic substrate in an arrangement facing the gas flow path. The catalyst layer comprises: The first catalyst promotes the Fischer-Tropsch reaction; and The second catalyst is capable of promoting the hydrocracking and / or isomerization of the hydrocarbon compound gas generated by the Fischer-Tropsch reaction.

2. The fuel manufacturing apparatus according to claim 1, wherein, The thermal conductivity of the ceramic substrate is above 0.4 W / m·K.

3. The fuel manufacturing apparatus according to claim 1, wherein, The catalyst layer has a monolayer structure in which the first catalyst and the second catalyst are dispersed.

4. The fuel manufacturing apparatus according to claim 1, wherein, The catalyst layer has a stacked structure, which includes a first catalyst layer containing the first catalyst and a second catalyst layer containing the second catalyst.

5. The fuel manufacturing apparatus according to any one of claims 1 to 4, wherein, The ceramic substrate is a honeycomb substrate having septa forming multiple pores, at least a portion of which includes the gas flow path. The catalyst layer is disposed on the surface of the partition wall.

6. The fuel manufacturing apparatus according to claim 5, wherein, The porosity of the partition wall is less than 65%.

7. The fuel manufacturing apparatus according to claim 6, wherein, The porosity of the partition wall is less than 10%.

8. The fuel manufacturing apparatus according to claim 5, wherein, The thickness of the partition wall is 0.0635 mm or more and 1.27 mm or less. The pore density in the honeycomb substrate is above 50 cpsi and below 900 cpsi.

9. The fuel manufacturing apparatus according to any one of claims 1 to 4, wherein, The raw material gas contains carbon monoxide as the carbon oxide.

10. The fuel manufacturing apparatus according to any one of claims 1 to 4, wherein, The raw material gas contains carbon dioxide as the carbon oxide. The catalyst layer contains a third catalyst that facilitates the reverse conversion reaction that converts carbon dioxide into carbon monoxide.

11. The fuel manufacturing apparatus according to any one of claims 1 to 4, wherein, The catalyst layer also includes filler. The thermal conductivity of the filler is 0.1 W / m·K to 500 W / m·K.

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