Fuel production device

Abstract

Provided is a fuel production device that can improve the conversion rate of carbon oxide and efficiently produce a synthetic fuel. The fuel production device according to an embodiment of the present invention has a first flow path. A raw material gas containing carbon oxide and hydrogen is supplied to the first flow path. The fuel production device comprises a first catalyst layer and a second catalyst layer. The first catalyst layer is disposed facing the first flow path. The first catalyst layer includes a first catalyst capable of promoting a Fischer-Tropsch reaction. The second catalyst layer is positioned on the opposite side of the first catalyst layer to the first flow path. The second catalyst layer includes a second catalyst capable of promoting the hydrocracking reaction and / or isomerization reaction of hydrocarbon compounds produced by the Fischer-Tropsch reaction.

Description

fuel production equipment

[0001] The present invention relates to a fuel production device.

[0002] In recent years, from the perspective of reducing environmental impact, studies have been conducted on recovering carbon oxides, including carbon dioxide and / or carbon monoxide, and using them as raw materials for hydrocarbon fuels. For example, a known method involves generating hydrocarbon compounds containing n-paraffins (linear alkanes) from carbon monoxide and hydrogen through the Fischer-Tropsch reaction (hereinafter referred to as the FT reaction), and then isomerizing the hydrocarbon compounds to produce synthetic fuels with an increased proportion of isoparaffins (branched alkanes). As a catalyst for use in producing such synthetic fuels, for example, a catalyst has been proposed that includes a Fischer-Tropsch synthesis catalyst having an alumina support and cobalt, and a beta zeolite membrane formed on the outer surface of the Fischer-Tropsch synthesis catalyst (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2017-144426

[0004] However, the catalyst described in Patent Document 1 has a problem in that a beta zeolite membrane is provided on the outer surface of the Fischer-Tropsch synthesis catalyst, which prevents the feed gas containing carbon monoxide and hydrogen from sufficiently contacting the Fischer-Tropsch synthesis catalyst. Therefore, the carbon monoxide conversion rate in the FT reaction is insufficient, and as a result, there is room for improvement in improving the efficiency of synthetic fuel production. The primary object of the present invention is to provide a fuel production apparatus that can improve the carbon oxide conversion rate and efficiently produce synthetic fuel.

[0005] [1] A fuel production apparatus according to one embodiment of the present invention has a first flow path. A feed gas containing carbon oxides and hydrogen is supplied to the first flow path. The fuel production apparatus includes a first catalyst layer and a second catalyst layer. The first catalyst layer is arranged facing the first flow path. The first catalyst layer includes a first catalyst capable of promoting a Fischer-Tropsch reaction. The second catalyst layer is located on the opposite side of the first catalyst layer from the first flow path. The second catalyst layer includes a second catalyst capable of promoting hydrocracking and / or isomerization of hydrocarbon compounds produced by the Fischer-Tropsch reaction. [2] The fuel production apparatus described in [1] above may further include a second flow path. The second flow path is located on the opposite side of the second catalyst layer from the first catalyst layer. A synthetic fuel produced by hydrocracking and / or isomerization of the hydrocarbon compounds may flow into the second flow path. [3] The fuel production apparatus described in [2] above may include a honeycomb structure. The honeycomb structure has a plurality of first cells including the first flow path and a plurality of second cells including the second flow path. [4] In the fuel production apparatus described in [3] above, each of the plurality of first cells and the plurality of second cells may extend from a first end face to a second end face of the honeycomb structure. The honeycomb structure may include first plugging portions. The first plugging portions are provided in at least a portion of the plurality of first cells. The first plugging portions plug the ends of the first flow paths on the second end face side. [5] In the fuel production apparatus described in [3] or [4] above, the honeycomb structure may further include second plugging portions. The second plugging portions are provided in at least a portion of the plurality of second cells. The second plugging portions plug the ends of the second flow paths on the first end face side. [6] In the fuel production apparatus according to any one of [3] to [5] above, the honeycomb structure may include a honeycomb substrate. The honeycomb substrate includes partition walls. The partition walls define the plurality of first cells and the plurality of second cells. The second catalyst layer may be laminated on a surface of the partition walls on the first flow path side. The first catalyst layer may be located on the opposite side of the second catalyst layer from the partition walls.The first catalyst layer may be laminated on the second catalyst layer. [7] In the fuel production apparatus according to [6] above, the porosity of the partition wall may be 25% to 70%. [8] In the fuel production apparatus according to [6] or [7] above, the thermal conductivity of the partition wall may be 0.4 W / mK or more. [9] In the fuel production apparatus according to [8] above, the thermal conductivity of the partition wall may be 8 W / mK or more.

[10] In the fuel production apparatus according to any one of [6] to [9] above, the partition wall may contain cordierite and / or SiC.

[11] In the fuel production apparatus according to any one of [6] to

[10] above, the partition wall may contain SiC.

[12] In the fuel production apparatus according to any one of [1] to

[11] above, the first catalyst may contain at least one transition metal.

[13] In the fuel production apparatus according to

[12] above, the transition metal may contain Co and / or Fe.

[14] In the fuel production apparatus according to any one of [1] to

[13] above, the second catalyst may contain zeolite.

[15] In the fuel production apparatus according to any one of [1] to

[14] above, the first catalyst layer and / or the second catalyst layer may further contain a filler. The thermal conductivity of the filler may be 0.1 W / m·K to 500 W / m·K.

[0006] According to an embodiment of the present invention, the carbon oxide conversion rate can be improved, and synthetic fuel can be produced efficiently.

[0007] Figure 1 is a schematic cross-sectional view of a fuel production apparatus according to one embodiment of the present invention. Figure 2 is a schematic cross-sectional view of a fuel production apparatus according to another embodiment of the present invention. Figure 3 is a schematic perspective view of a fuel production apparatus according to yet another embodiment of the present invention. Figure 4 is a schematic cross-sectional view of the fuel production apparatus of Figure 3. Figure 5 is a schematic cross-sectional view of a fuel production apparatus according to yet another embodiment of the present invention. Figure 6 is a schematic cross-sectional view of a fuel production apparatus according to yet another embodiment of the present invention. Figure 7 is a schematic cross-sectional view of a fuel production apparatus according to yet another embodiment of the present invention. Figure 8 is a schematic cross-sectional view of a fuel production apparatus according to yet another embodiment of the present invention.

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to these embodiments. In addition, in order to clarify the description, the drawings may show the width, thickness, shape, etc. of each part more schematically than in the embodiment, but these are merely examples and do not limit the interpretation of the present invention.

[0009] A. Overview of the Fuel Production Apparatus As shown in FIG. 1, in one embodiment, the fuel production apparatus 100 has a first flow path 4. A raw material gas containing carbon oxides and hydrogen is supplied to the first flow path 4. The carbon oxides include carbon monoxide (CO) and carbon dioxide (CO ２ ) are examples. The raw material gas typically contains carbon monoxide. The fuel production device 100 includes a first catalyst layer 1 and a second catalyst layer 2. The first catalyst layer 1 is disposed facing the first flow path 4. The first catalyst layer 1 contains a first catalyst capable of promoting the FT reaction. The second catalyst layer 2 is located on the opposite side of the first catalyst layer 1 from the first flow path 4. The second catalyst layer 2 contains a second catalyst capable of promoting the hydrocracking reaction and / or isomerization reaction of hydrocarbon compounds produced by the FT reaction. With this configuration, the first catalyst layer containing the first catalyst capable of promoting the FT reaction faces the first flow path, allowing the raw material gas to stably contact the first catalyst. Therefore, the FT reaction shown in the following formula (1) can proceed smoothly, and the conversion rate of carbon monoxide can be improved. nCO + (2n + 1)H ２ →C ｎ H ２ｎ＋２ +nH ２ O... (1) This results in alkanes (C ｎ H ２ｎ＋２ ) is produced. ｎ H ２ｎ＋２where n represents an integer of 1 or greater. Hydrocarbon compounds typically contain n-paraffins (linear alkanes) and isoparaffins (branched alkanes). When these hydrocarbon compounds reach the second catalyst contained in the second catalyst layer, at least a portion of the n-paraffins is hydrocracking and / or isomerization converting them to isoparaffins. This increases the proportion of isoparaffins present, making it possible to efficiently produce synthetic fuels containing sufficient isoparaffins. As a result, it is possible to improve the selectivity of fuel components with 5 to 20 carbon atoms in the synthetic fuel (hereinafter referred to as C5 to C20 selectivity), and it is also possible to improve the isoparaffin ratio in the synthetic fuel.

[0010] As shown in FIG. 2 , in one embodiment, the fuel production apparatus 101 further includes a second flow path 5 in addition to the first flow path 4. The second flow path 5 is located on the opposite side of the second catalyst layer 2 from the first catalyst layer 1. The synthetic fuel produced by the hydrocracking reaction and / or isomerization reaction of the hydrocarbon compounds typically flows into the second flow path 5 in a gaseous state. With this configuration, the fluid flowing through the fuel production apparatus flows from the first flow path through the first and second catalyst layers in this order and into the second flow path. Therefore, the feed gas supplied to the first flow path passes through the first catalyst layer and comes into stable contact with the first catalyst contained in the first catalyst layer. As a result, hydrocarbon compounds are efficiently produced from the feed gas. The produced hydrocarbon compounds typically flow in a gaseous state through the second catalyst layer and come into stable contact with the second catalyst contained in the second catalyst layer. This allows for efficient production of synthetic fuel from the hydrocarbon compounds. The synthetic fuel then flows into the second flow path, typically in gaseous form, so that the synthetic fuel can be easily withdrawn from the second flow path.

[0011] As shown in Figures 3 and 4, in one embodiment, a fuel production apparatus 102 includes a honeycomb structure 10. The honeycomb structure 10 has a plurality of first cells 321 including first flow paths 4 and a plurality of second cells 322 including second flow paths 5. With this configuration, raw material gas can be supplied to the plurality of first flow paths and synthetic fuel gas can be recovered from the plurality of second flow paths, so the reaction area is increased compared to the fuel production apparatus shown in Figure 2, and the reaction can proceed more efficiently. As a result, synthetic fuel can be efficiently produced and recovered.

[0012] As shown in Figure 4, each of the multiple first cells 321 and the multiple second cells 322 typically extends in the longitudinal direction (axial direction) of the honeycomb structure 10 from a first end face E1 (inlet end face) to a second end face E2 (outlet end face) of the honeycomb structure 10.

[0013] As shown in FIG. 5 , in one embodiment, the fuel production device 102 further includes a first sealing portion 6. The first sealing portion 6 is provided in at least some of the plurality of first cells 321. In the illustrated example, the first sealing portion 6 is provided in all of the plurality of first cells 321. The first sealing portion 6 seals the end of the first flow path 4 on the second end face E2 (outlet end face). With this configuration, the first sealing portion seals the end of the first flow path on the outlet end face side. Therefore, in the fuel production device, the fluid can stably flow from the first flow path through the first catalyst layer and the second catalyst layer in this order and into the second flow path. This allows for more efficient production of synthetic fuel.

[0014] The fuel production device 102 may further include a second sealing unit 7. The second sealing unit 7 is provided in at least some of the multiple second cells 322. In the illustrated example, the second sealing unit 7 is provided in all of the multiple second cells 322. The second sealing unit 7 seals the end of the second flow path 5 on the first end face E1 (inlet end face). With this configuration, the second sealing unit seals the end of the second flow path on the inlet end face side, which can prevent the raw material gas from accidentally flowing into the second flow path. Therefore, the raw material gas can be stably supplied to the first flow path, and synthetic fuel gas can be produced more efficiently.

[0015] B. Details of the Fuel Production Apparatus Next, the fuel production apparatuses 100, 101, and 102 will be described in detail with reference to FIGS.

[0016] B-1. Details of the fuel production apparatus 100 As shown in Fig. 1, the fuel production apparatus 100 has a flow-through configuration. In one embodiment, the fuel production apparatus 100 includes a substrate 3, a second catalyst layer 2, and a first catalyst layer 1. The substrate 3 supports the first catalyst layer 1 and / or the second catalyst layer 2.

[0017] In the illustrated example, the substrate 3 is a cylindrical substrate 3a having a cylindrical shape extending in a predetermined direction. The cylindrical substrate 3a has any appropriate shape in a cross section perpendicular to the longitudinal direction. Examples of the cross-sectional shape of the cylindrical substrate 3a include a triangle, a rectangle, a pentagon, a polygon with hexagons or more, a circle, and an ellipse.

[0018] The cylindrical substrate 3a includes a first flow path 4. The first flow path 4 is a space formed inside the cylindrical substrate 3a. In one embodiment, the first flow path 4 is formed in a portion of the cross section of the cylindrical substrate 3a where the first catalyst layer 1 and the second catalyst layer 2 are not formed (typically the central portion). The first flow path 4 extends from the first end face E1 (inlet end face) to the second end face E2 (outlet end face) of the fuel production apparatus. The first flow path 4 has any appropriate shape in a cross section perpendicular to the length direction. Examples of the cross-sectional shape of the first flow path 4 include the same cross-sectional shape as that of the cylindrical substrate 3a described above.

[0019] The cylindrical substrate 3a is configured to be substantially impermeable to synthetic fuel gas. The thickness of the cylindrical substrate 3a is, for example, 0.1 mm to 10 mm, for example, 0.2 mm to 8 mm, or for example, 0.5 mm to 5 mm. The thickness is measured, for example, by cross-sectional observation using a scanning electron microscope (SEM). The average pore diameter in the cylindrical substrate 3a is, for example, 0.05 μm to 1000 μm. The average pore diameter is measured, for example, by mercury intrusion porosimetry. The porosity in the cylindrical substrate 3a is, for example, 0% to 50%. The porosity can be measured, for example, by mercury intrusion porosimetry. If the average pore diameter and / or porosity of the cylindrical substrate are within these ranges, the synthetic fuel can be prevented from permeating the cylindrical substrate and leaking from the first flow path.

[0020] The cylindrical substrate 3a is made of any appropriate material. Examples of materials constituting the cylindrical substrate 3a include metal materials and ceramic materials. Examples of metal materials include stainless steel (SUS) and nickel alloys. Examples of ceramic materials include cordierite, SiC, Si-SiC composite materials, mullite, alumina, spinel, silicon carbide-cordierite composite materials, lithium aluminum silicate, aluminum titanate, silicon nitride, and zirconia. The ceramic materials may be used alone or in combination. Examples of materials for the cylindrical substrate 3a include preferably ceramic materials, more preferably cordierite, SiC, and Si-SiC composite materials, and even more preferably Si-SiC composite materials.

[0021] The thermal conductivity of the cylindrical substrate 3a is, for example, 0.1 W / mK or more, preferably 0.4 W / mK or more, more preferably 8.0 W / mK or more, and even more preferably 100 W / mK or more. On the other hand, the upper limit of the thermal conductivity of the cylindrical substrate 3a is typically 500 W / mK. When the thermal conductivity of the cylindrical substrate is in this range, the temperature of the fuel production apparatus can be uniformly adjusted during the production of synthetic fuel. Therefore, the desired synthetic fuel can be stably produced.

[0022] In one embodiment, the second catalytic layer 2 is provided on the inner surface of the cylindrical substrate 3 a. The second catalytic layer 2 may be provided on the entire inner surface of the cylindrical substrate 3 a, or on a part of the inner surface of the cylindrical substrate 3 a.

[0023] The second catalyst layer 2 contains a second catalyst capable of promoting the hydrocracking reaction and / or isomerization reaction of the hydrocarbon compounds. Examples of the second catalyst include zeolite, silica-alumina, silica, alumina, titania, vanadium oxide, and molybdenum oxide. The second catalyst may be used alone or in combination.

[0024] In one embodiment, the second catalyst includes a zeolite. When the second catalyst includes a zeolite, the second catalyst can stably hydrocracking and / or isomerize hydrocarbon compounds.

[0025] Examples of zeolites include β-type zeolite, ZSM-5-type zeolite, USY-type zeolite, and mordenite-type zeolite, and preferably β-type zeolite and ZSM-5-type zeolite.

[0026] The maximum number of ring members in the zeolite is, for example, 6 to 16, preferably 8 to 14, and more preferably 10 to 12.

[0027] Zeolite is SiO ２ and Al ２ O ３ SiO in zeolite ２ / Al ２ O ３ The molar ratio of SiO in zeolite is, for example, 5 to 2000, preferably 10 to 1500. ２ / Al ２ O ３ When the molar ratio of SiO is within this range, the hydrocarbon compound can be hydrocracking and / or isomerization more stably. ２ / Al ２ O ３ The molar ratio is measured, for example, by scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDX; X-ray acceleration voltage 10 kV).

[0028] The content of the second catalyst in the second catalyst layer 2 is, for example, 30% by mass to 100% by mass, and preferably 80% by mass to 100% by mass. When the content of the second catalyst is within this range, the hydrocracking and / or isomerization of hydrocarbon compounds can be performed more stably.

[0029] The thermal conductivity of the second catalyst layer 2 is, for example, 0.01 W / m·K to 40 W / m·K, and preferably 0.1 W / m·K to 40 W / m·K.

[0030] The second catalyst layer 2 may contain an additive in addition to the second catalyst. Examples of the additive include a filler, a binder, and a sintering inhibitor. The additives may be used alone or in combination. The additive content is, for example, 0 to 70 parts by mass, and preferably 0 to 20 parts by mass, per 100 parts by mass of the second catalyst.

[0031] Such a second catalytic layer 2 can be prepared by any appropriate method, such as a coating method in which a material for the second catalytic layer is applied to a substrate to form the second catalytic layer, or a reaction method in which the second catalytic layer is formed by a reaction such as hydrothermal synthesis.

[0032] When the second catalytic layer 2 is prepared by a coating method, the average pore size of the second catalytic layer 2 is, for example, 0.8 μm to 25 μm, and preferably 1 μm to 20 μm. The porosity of the second catalytic layer 2 is, for example, 30% to 80%, and preferably 30% to 70%. The thickness of the second catalytic layer 2 is, for example, 3 μm to 200 μm, and preferably 5 μm to 100 μm.

[0033] On the other hand, when the second catalyst layer 2 is prepared by a reaction method, the second catalyst layer 2 is configured as a denser thin film than when prepared by a coating method. The thickness of the second catalyst layer 2 is, for example, 1 μm to 80 μm, and preferably 2 μm to 50 μm.

[0034] In one embodiment, the first catalytic layer 1 is provided on the surface of the second catalytic layer 2 opposite to the cylindrical substrate 3a (substrate 3). The first catalytic layer 1 may be provided on the entire surface of the second catalytic layer 2 opposite to the cylindrical substrate 3a, or on a part of the surface. In the illustrated example, the first catalytic layer 1 is provided on the entire surface of the second catalytic layer 2 opposite to the cylindrical substrate 3a. This allows the above-mentioned hydrocarbon compounds to be stably produced from the feed gas.

[0035] The first catalyst layer 1 contains a first catalyst capable of promoting the FT reaction. The first catalyst typically contains any suitable active component. Examples of the active component include transition metals, noble metals, rare earth elements, alkali metals, and alkaline earth metals. The active components may be used alone or in combination. 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. The first catalyst may contain these elements in a metallic state (e.g., pure metal or alloy) or in a compound state (e.g., oxide or carbide). The first catalyst preferably contains a transition metal, such as Co, Fe, Ni, or Ru, either singly or in combination. When the first catalyst contains at least one suitable transition metal, the hydrocarbon compounds described above can be produced more stably from the feed gas.

[0036] In one embodiment, the first catalyst contains Co and / or Fe. When the first catalyst contains Co and / or Fe, the activity of the first catalyst can be improved. In particular, when the first catalyst contains Co, the activity of the first catalyst can be further improved.

[0037] The first catalyst may further contain a support in addition to the active component described above. The support is capable of supporting the active component. 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. The inorganic materials may be used alone or in combination.

[0038] In one embodiment, the support is composed of an inorganic oxide. Examples of inorganic oxides include aluminum oxide, silicon oxide, magnesium oxide, titanium oxide, cerium oxide, zirconium oxide, and composite oxides thereof. Among the inorganic oxides, aluminum oxide is preferred.

[0039] The BET specific surface area of ​​such a support is, for example, 10 m ２ / g~1500m ２ / g, preferably 30m ２ / g~1200m ２ / g, more preferably 60m ２ / g to 1000m ２ / g. If the BET specific surface area of ​​the support is within this range, the support can support the active component in a sufficiently dispersed state, and the activity of the first catalyst can be further improved. The pore diameter of the support is, for example, 3 nm to 50 nm, preferably 5 nm to 40 nm, and more preferably 7 nm to 30 nm. The pore volume of the support 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. The pore volume is measured, for example, by mercury intrusion porosimetry or water titration.

[0040] When the first catalyst contains an active component and a support, the content of the active component in the first catalyst is, for example, 1 to 30 parts by mass, and preferably 5 to 20 parts by mass, relative to 100 parts by mass of the support. When the content of the active component is within this range, the FT reaction can be stably promoted.

[0041] The content of the first catalyst in the first catalyst layer 1 is, for example, 30% by mass to 100% by mass, and preferably 80% by mass to 100% by mass. When the content of the first catalyst is in this range, the hydrocarbon compounds described above can be produced from the raw material gas more stably.

[0042] The thermal conductivity of the first catalyst layer 1 is, for example, 0.01 W / m·K to 40 W / m·K, and preferably 0.1 W / m·K to 40 W / m·K.

[0043] The first catalyst layer 1 may contain an additive in addition to the first catalyst. Examples of the additive include a filler, a binder, a sintering inhibitor, and a promoter. The additives may be used alone or in combination. The additive content is, for example, 0 to 70 parts by mass, preferably 0 to 50 parts by mass, and more preferably 5 to 30 parts by mass, relative to 100 parts by mass of the first catalyst.

[0044] In one embodiment, the first catalyst layer 1 and / or the second catalyst layer 2 contains a filler. Examples of the filler include Al ２ O ３ , AlN, BN, BeO, SiC, Si, Al, Au, Cu, Ag, Si ３ N ４ , SiO ２ , ZnO, MgO, and carbon, and preferably Al ２ O ３, AlN, and BN. The fillers can be used alone or in combination. 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. When the first catalytic layer and / or the second catalytic layer contains a filler with such a thermal conductivity, the thermal conductivity of the first catalytic layer and / or the second catalytic layer can be stably adjusted within the above-mentioned range. 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, 1,000 nm or less, preferably 500 nm or less. The aspect ratio of the filler is, for example, 1.0 or more, preferably 1.2 or more, and more preferably 1.5 or more. On the other hand, the aspect ratio of the filler is, for example, 500 or less, preferably 300 or less.

[0045] The thickness of the first catalytic layer 1 is, for example, 3 μm to 200 μm, and preferably 5 μm to 150 μm. The average pore diameter in the first catalytic layer 1 is, for example, 0.8 μm to 25 μm, and preferably 1 μm to 20 μm. The porosity in the first catalytic layer 1 is, for example, 30% to 80%, and preferably 30% to 70%.

[0046] B-2. Details of the fuel production apparatus 101 As shown in Fig. 2, the fuel production apparatus 101 has a wall-flow configuration. In one embodiment, the fuel production apparatus 101 includes a continuous cylinder substrate 3b as the substrate 3, in addition to the first catalyst layer 1 and the second catalyst layer 2 described above. The continuous cylinder substrate 3b has first cells 321 and second cells 322.

[0047] The first cell 321 includes the first flow path 4. The first cell 321 can be described in the same manner as the cylindrical substrate 3 a. In the illustrated example, the second catalyst layer 2 and the first catalyst layer 1 are laminated in this order on the inner surface of the first cell 321.

[0048] The second cell 322 includes the second flow path 5 described above. The second cell 322 can be described similarly to the first cell 321 described above, except that the second cell 322 does not include the first catalyst layer 1 and the second catalyst layer 2. The second flow path 5 is a space formed inside the second cell 322. In the illustrated example, the second flow path 5 is defined by the inner surface of the second cell 322. The second flow path 5 extends from the first end face E1 (inlet end face) to the second end face E2 (outlet end face) of the fuel production apparatus. The second flow path 5 has any appropriate shape in a cross section perpendicular to the longitudinal direction. Examples of the cross-sectional shape of the second flow path 5 include a cross-sectional shape similar to that of the first flow path 4 described above. The cross-sectional area of ​​the second flow path 5 may be the same as or different from the cross-sectional area of ​​the first flow path 4.

[0049] In the illustrated example, the first cell 321 and the second cell 322 are connected to each other so as to share the partition wall 31. The partition wall 31 is located between the first flow path 4 and the second flow path 5. Therefore, the fluid flowing through the fuel production device 101 flows from the first flow path 4 through the partition wall 31 into the second flow path 5.

[0050] The partition walls 31 are configured to be substantially permeable to synthetic fuel (typically, synthetic fuel gas). The thickness of the partition walls 31 is, for example, 60 μm to 550 μm, and preferably 150 μm to 510 μm. The average pore diameter in the partition walls 31 is, for example, 5 μm to 30 μm, and preferably 8 μm to 25 μm. The porosity in the partition walls 31 is, for example, 20% to 75%, and preferably 25% to 70%. When the average pore diameter and / or the porosity are within these ranges in the partition walls, the synthetic fuel gas can stably permeate through them.

[0051] The continuous cylindrical substrate 3b is typically made of the ceramic material described above. The range of thermal conductivity of the continuous cylindrical substrate 3b is, for example, the same as the range of thermal conductivity of the cylindrical substrate 3a described above.

[0052] B-3. ​​Details of the fuel production apparatus 102 As shown in Figures 3 and 4, the fuel production apparatus 102 has a wall-flow type configuration. In one embodiment, the honeycomb structure 10 included in the fuel production apparatus 102 includes a honeycomb substrate 3c as the substrate 3, in addition to the first catalyst layer 1 and the second catalyst layer 2. The honeycomb substrate 3c includes partition walls 31 that define a plurality of first cells 321 and a plurality of second cells 322.

[0053] The first cells 321 and the second cells 322 included in the honeycomb substrate 3c can be described in the same manner as the first cells 321 and the second cells 322 included in the continuous-cylinder substrate 3b. The second catalyst layer 2 and the first catalyst layer 1 are laminated in this order on the inner surface of each of the plurality of first cells 321.

[0054] In the honeycomb substrate 3c, the first cells 321 and the second cells 322 are arranged arbitrarily and appropriately depending on the application. The first cells 321 and the second cells 322 are typically arranged alternately.

[0055] The honeycomb substrate 3c may have any appropriate shape (overall shape). Examples of the shape of the honeycomb substrate 3c include a cylindrical shape with a circular bottom, an elliptical cylindrical shape with an elliptical bottom, a rectangular prism shape with a polygonal bottom, and a cylindrical shape with an irregular bottom. In one embodiment, the honeycomb substrate 3c has a cylindrical shape. The outer diameter and length of the honeycomb substrate 3c can be appropriately set depending on the purpose.

[0056] The cell density of the honeycomb substrate 3c is, for example, 150 cpsi or more, preferably 200 cpsi or more, and more preferably 300 cpsi or more. On the other hand, the cell density of the honeycomb substrate 3c is, for example, 1200 cpsi or less, and preferably 900 cpsi or less. In this specification, the "cell density of the honeycomb structure" means the cell density of a cross section in the length direction (cell extension direction) of the honeycomb structure, and "cpsi" means the cell density of 6.4516 cm of the cross section. ２ This refers to the total number of first cells and second cells per square inch.

[0057] In the illustrated example, the honeycomb substrate 3c includes outer walls 33 and partition walls 31. The outer walls 33 and the partition walls 31 may be integrally formed or may be separate bodies. In the illustrated example, the outer walls 33 and the partition walls 31 are integrally formed.

[0058] The outer wall 33 has a cylindrical shape. The thickness of the outer wall 33 can be appropriately set depending on the application of the fuel production apparatus. 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.

[0059] The partition walls 31 are located inside the outer wall 33. In the illustrated example, the partition walls 31 have first partition walls 311 and second partition walls 312 that are perpendicular to each other, and the first partition walls 311 and the second partition walls 312 define a plurality of first cells 321 and a plurality of second cells 322. Examples of the cross-sectional shape of each of the first cells 321 and the second cells 322 include a triangle, a rectangle, a pentagon, a polygon having hexagons or more, a circle, and an ellipse. In the illustrated example, the cross-sectional shape of each of the first cells 321 and the second cells 322 is a rectangle except for the portions where the first partition walls 311 and the second partition walls 312 contact the outer wall 33. Note that the configuration of the partition walls is not limited to the above-described partition walls 31. The partition walls may have first partition walls extending in the radial direction and second partition walls extending in the circumferential direction, which define a plurality of cells.

[0060] The partition walls 31 are configured to be substantially permeable to synthetic fuel gas. The thickness range of the partition walls 31 of the honeycomb substrate 3c is, for example, the same as the thickness range of the partition walls 31 of the continuous-cylinder substrate 3b described above. The average pore diameter range of the partition walls 31 of the honeycomb substrate 3c is, for example, the same as the average pore diameter range of the partition walls 31 of the continuous-cylinder substrate 3b described above. The porosity range of the partition walls 31 of the honeycomb substrate 3c is, for example, the same as the porosity range of the partition walls 31 of the continuous-cylinder substrate 3b described above. The porosity of the partition walls 31 of the honeycomb substrate 3c is preferably 25% to 70%. When the average pore diameter and / or porosity of the partition walls are within these ranges, synthetic fuel gas can stably permeate through them.

[0061] The partition walls 31 are typically made of the ceramic material described above. In one embodiment, the partition walls 31 contain cordierite and / or SiC. When the partition walls contain cordierite and / or SiC, the thermal conductivity of the partition walls can be improved. In particular, when the partition walls contain SiC, the thermal conductivity of the partition walls can be significantly improved.

[0062] The thermal conductivity of the partition wall 31 is, for example, 0.1 W / mK or more, preferably 0.4 W / mK or more, and more preferably 8.0 W / mK or more. On the other hand, the upper limit of the thermal conductivity of the partition wall 31 is typically 40 W / mK. When the thermal conductivity of the partition wall is in this range, the temperature of the fuel production apparatus can be adjusted more uniformly during the production of synthetic fuel. Therefore, the desired synthetic fuel can be stably produced.

[0063] 4 , in one embodiment, the second catalyst layer 2 is laminated on the surface of the partition wall 31 on the first flow path 4 side. The first catalyst layer 1 is located on the opposite side of the partition wall 31 with respect to the second catalyst layer 2, and is laminated on the second catalyst layer 2. With such a configuration, the first catalyst layer and the second catalyst layer are in direct contact with each other, and therefore, during the production of synthetic fuel, deposition of paraffin wax having a carbon number of 20 or more can be suppressed, and clogging of the first catalyst layer and / or the second catalyst layer with the paraffin wax can be suppressed.

[0064] 5, the fuel production apparatus 102 may further include a first sealing portion 6 and / or a second sealing portion 7. Each of the first sealing portion 6 and the second sealing portion 7 is configured to be substantially impermeable to the source gas.

[0065] The first sealing portion 6 is made of any appropriate material. Examples of materials that can be used for the first sealing portion 6 include the ceramic materials described above. The materials that can be used for the first sealing portion 6 can be used alone or in combination. In the illustrated example, the first sealing portion 6 is fixed to the partition wall 31. The first sealing portion 6 may be formed integrally with the partition wall 31, or may be separate from the partition wall 31. In one embodiment, the first sealing portion 6 is formed integrally with the partition wall 31.

[0066] The dimension of the first sealing portion 6 in the extension direction of the first cells 321 is typically larger than the thickness of the partition wall 31. The dimension of the first sealing portion 6 in the extension direction of the first cells 321 is, for example, two times or more, preferably three times or more, the thickness of the partition wall 31. When the first sealing portion has such dimensions, permeation of the source gas can be sufficiently suppressed. On the other hand, the dimension of the first sealing portion 6 in the extension direction of the first cells 321 is, for example, 180 times or less, preferably 160 times or less, the thickness of the partition wall 31.

[0067] The second sealing portion 7 is made of any appropriate material. Examples of materials that can be used for the second sealing portion 7 include the same materials as those used for the first sealing portion 6 described above. The materials that can be used for the second sealing portion 7 can be used alone or in combination. In the illustrated example, the second sealing portion 7 is fixed to the partition wall 31. The second sealing portion 7 may be formed integrally with the partition wall 31, or may be separate from the partition wall 31. In one embodiment, the second sealing portion 7 is formed integrally with the partition wall 31.

[0068] The dimension of the second sealing portion 7 in the extension direction of the second cells 322 is typically larger than the thickness of the partition wall 31. The range of the dimension of the second sealing portion 7 in the extension direction of the second cells 322 is, for example, the same as the range of the dimension of the first sealing portion 6 described above. When the second sealing portion has such dimensions, permeation of the source gas can be sufficiently suppressed.

[0069] B-4. Modification In the fuel production apparatus 102, the second catalyst layer 2 is laminated on the surface of the partition wall 31 on the side of the first flow passage 4. The arrangement of the second catalyst layer 2 is not limited to this. As shown in FIG. 6 , the second catalyst layer 2 may be laminated on the surface of the partition wall 31 on the side of the second flow passage 5. In this case, the second catalyst layer 2 is typically arranged to face the second flow passage 5. The second catalyst layer 2 is located on the opposite side of the partition wall 31 from the first catalyst layer 1. This also makes it possible to improve the carbon oxide conversion rate and efficiently produce synthetic fuel.

[0070] As shown in FIG. 5 , the honeycomb structure 10 included in the fuel production device 102 includes a first catalyst layer 1, a second catalyst layer 2, and a honeycomb substrate 3c. The configuration of the honeycomb structure 10 is not limited to this. As shown in FIG. 7 , the honeycomb substrate 3c may be formed from the second catalyst described above. In this case, the partition walls 31 included in the honeycomb substrate 3c function as the second catalyst layer 2. In the illustrated example, the honeycomb structure 11 is formed from the first catalyst layer 1 and a honeycomb substrate having partition walls 31 (second catalyst layer 2) formed from the second catalyst. This also improves the carbon oxide conversion rate and enables efficient production of synthetic fuel.

[0071] 1 includes one first flow path 4. The number of first flow paths 4 is not limited to this. As shown in FIG. 8, the fuel production device 100 may include a plurality of first flow paths 4. In the illustrated example, the substrate 3 has a plurality of cells 32 including the first flow paths 4. Each of the plurality of cells 32 can be described in the same manner as the above-described first cell 321. In other words, the above-described second catalyst layer 2 and the above-described first catalyst layer 1 are stacked in this order on the inner surface of each of the plurality of cells 32.

[0072] Furthermore, the first catalyst layer 1 may further include a third catalyst capable of promoting a reverse shift reaction that converts carbon dioxide into carbon monoxide, in addition to the first catalyst described above. In this case, when a raw material gas containing carbon dioxide and hydrogen is supplied to the first flow path 4, the third catalyst smoothly promotes the reverse shift reaction shown in the following formula (2), producing carbon monoxide. ２ +H ２ →CO+H ２ O (2) Then, the FT reaction shown in formula (1) above proceeds in the presence of the first catalyst. Therefore, synthetic fuel gas can be efficiently produced from the feed gas containing carbon dioxide.

[0073] C. Method for Producing Synthetic Fuel Next, for convenience, a method for producing synthetic fuel according to one embodiment will be described with reference to the fuel production apparatus 102 shown in Figure 5. In one embodiment, the fuel production apparatus 102 is heated to a predetermined FT reaction initiation temperature. The FT reaction initiation temperature is, for example, 200°C to 400°C.

[0074] Next, the raw material gas containing carbon monoxide and hydrogen is supplied to the first flow path 4 of the fuel production device 102 .

[0075] The carbon monoxide content in the source gas is, for example, 25% to 50% by volume, and preferably 28% to 40% by volume. The hydrogen content in the source gas is, for example, 50% to 75% by volume, and preferably 60% to 72% by volume. The pressure in the first flow path 4 is, for example, 0.7 MPa (absolute pressure) to 4.0 MPa (absolute pressure), and preferably 0.8 MPa (absolute pressure) to 3.5 MPa (absolute pressure).

[0076] As a result, the raw material gas comes into contact with the first catalyst layer 1 at the FT reaction initiation temperature, and the FT reaction of formula (1) above begins. This typically produces hydrocarbon compounds containing n-paraffins and isoparaffins. Among the hydrocarbon compounds, n-paraffins have, for example, 1 to 25 carbon atoms, and isoparaffins have, for example, 4 to 20 carbon atoms.

[0077] Furthermore, when the first catalyst layer 1 contains a third catalyst, a feed gas containing carbon dioxide and hydrogen is supplied to the first flow path 4 of the fuel production device 102. In this case, the carbon dioxide content in the feed gas is, for example, 20% to 40% by volume, and preferably 22% to 29% by volume. The hydrogen content in the feed gas is, for example, 60% to 80% by volume, and preferably 71% to 78% by volume.

[0078] As a result, the raw material gas comes into contact with the first catalyst layer 1, and the reverse shift reaction of the above formula (2) and the FT reaction of the above formula (1) start in this order, producing hydrocarbon compounds including n-paraffins and isoparaffins.

[0079] The content of n-paraffins in the hydrocarbon compound is, for example, 30% to 100% by volume. The content of isoparaffins in the hydrocarbon compound is, for example, 0% to 15% by volume, and preferably 0% to 10% by volume. The hydrocarbon compound may further contain an olefin (alkene). In the hydrocarbon compound, the number of carbon atoms of the olefin is, for example, 3 to 10. The content of olefins in the hydrocarbon compound is, for example, 0% to 70% by volume, and preferably 0% to 60% by volume.

[0080] When these hydrocarbon compounds reach the second catalyst layer 2, the n-paraffins are hydrocracking and / or isomerization to convert them to isoparaffins. At this time, the n-paraffins may also be converted to olefins. This produces a synthetic fuel containing a sufficient amount of isoparaffins. In the synthetic fuel, the carbon numbers of the n-paraffins, isoparaffins, and olefins are, for example, 4 to 15, and preferably 5 to 12. The synthetic fuel is typically produced as a synthetic fuel gas. The n-paraffin content in the synthetic fuel gas is, for example, less than 80% by volume, and preferably 70% by volume or less. Meanwhile, the n-paraffin content in the synthetic fuel gas is, for example, 0% by volume or more, and, for example, 10% by volume or more. The isoparaffin content in the synthetic fuel gas is, for example, more than 15% by volume, and preferably 20% by volume or more. Meanwhile, the isoparaffin content in the synthetic fuel gas is, for example, 100% by volume or less, and, for example, less than 85% by volume, and, for example, 80% by volume or less. The olefin content in the synthetic fuel gas is, for example, 0% by volume or more, preferably more than 5% by volume, and preferably 10% by volume or more, while the olefin content in the synthetic fuel gas is, for example, less than 85% by volume, for example, 80% by volume or less, or for example, 70% by volume or less.

[0081] Such synthetic fuel typically flows in a gaseous state from the first flow path 4 to the second flow path 5 and is then continuously discharged from the second flow path 5. In one embodiment of the fuel production apparatus, the first catalyst layer is disposed facing the first flow path, so that the synthetic fuel can be produced with an excellent conversion rate. The carbon oxide conversion rate that can be achieved by the fuel production apparatus is, for example, 65% or more, preferably 70% or more, and more preferably 75% or more. Meanwhile, the upper limit of the carbon oxide conversion rate is 100%.

[0082] The present invention will be specifically explained below with reference to examples, but the present invention is not limited to these examples.

[0083] Example 1 Preparation of Honeycomb Substrate 80 parts by mass of SiC raw material powder and 20 parts by mass of metal Si powder were extruded into a clay, dried, and calcined at 550°C for 3 hours in an oxidizing atmosphere, followed by firing at 1450°C for 2 hours in a non-oxidizing atmosphere. A honeycomb substrate was thus prepared. The honeycomb substrate had partition walls defining a plurality of first cells and a plurality of second cells, and an outer wall surrounding the partition walls. The cross-sectional shape of the cells was rectangular. The cell density of the honeycomb substrate was 300 cpsi, and the partition wall thickness was 0.254 mm. The honeycomb substrate was composed of a porous body of a Si-SiC composite material. The partition wall thickness of the honeycomb substrate was 0.254 mm, the average pore diameter of the partition walls was 28 μm, and the porosity of the partition walls was 63%. The thermal conductivity of the honeycomb substrate is shown in Table 1. Furthermore, the honeycomb substrate was provided with a plurality of first plugs and a plurality of second plugs, wherein the first plugs plugged the ends of the first cells on the second end face side, and the second plugs plugged the ends of the second cells on the first end face side.

[0084] <<Preparation of Second Catalyst Layer>> Commercially available HZSM-5 (zeolite, manufactured by Nakamura Choukou Co., Ltd.) was calcined in an electric furnace at 500°C for 4 hours to obtain second catalyst particles. The obtained second catalyst particles were dispersed in distilled water to prepare a second catalyst slurry. The catalyst particle content in the second catalyst slurry was 10 mass%. Next, the second catalyst slurry was flowed into the multiple first cells of the honeycomb substrate prepared above at normal pressure (0.1 MPa) and room temperature (23°C). This resulted in the second catalyst slurry being applied to the partition wall surfaces. The first catalyst slurry applied to the partition wall surfaces was then heated and dried at 100°C for 120 minutes. The above application and drying processes were repeated to form a second catalyst layer on the partition wall surfaces. The second catalyst layer contained aggregates of the second catalyst particles. The thickness of the second catalyst layer was 80 μm. The amount of the second catalyst particles supported per unit area of ​​the partition wall is 0.011 g / cm ２ It was.

[0085] <<Preparation of First Catalyst Layer>> Silicon dioxide (IV) particles were introduced into distilled water, and then the mixture was stirred under reduced pressure at room temperature (23°C) for 12 hours. This resulted in a dispersion of metal oxide particles. Cobalt (II) nitrate hexahydrate was also dissolved in distilled water to obtain an aqueous cobalt nitrate solution. Next, the aqueous cobalt nitrate solution was added to the dispersion of metal oxide particles, and the mixture was stirred at room temperature (23°C) for 2 hours. Thereafter, the mixture of the dispersion and the aqueous solution was heated to 80°C while stirring to evaporate the water. Next, the remaining solid was heated at 500°C for 3 hours. This resulted in a first catalyst. The first catalyst particles were composed of tricobalt tetroxide (Co ３ O ４ ) and tricobalt tetroxide (Co ３ O ４The first catalyst particles contained 20 parts by mass of Co based on 100 parts by mass of silicon dioxide. The first catalyst particles were dispersed in distilled water to prepare a first catalyst slurry. The catalyst particle content in the first catalyst slurry was 10% by mass. The first catalyst slurry was then flowed into the first cell containing the second catalyst layer at normal pressure (0.1 MPa) and room temperature (23°C). This resulted in the second catalyst slurry being applied to the surface of the second catalyst layer. The first catalyst slurry applied to the surface of the second catalyst layer was then heated and dried at 100°C for 120 minutes. The above-described application and drying processes were repeated to form a first catalyst layer on the surface of the second catalyst layer. The first catalyst layer contained aggregates of the first catalyst particles. The thickness of the first catalyst layer was 150 μm. The amount of the first catalyst particles supported per unit area of ​​the partition wall is 0.011 g / cm ２ In this way, the fuel production apparatus shown in Fig. 5 was manufactured, which was provided with a honeycomb substrate, a first catalyst layer, and a second catalyst layer.

[0086] Example 2 The first catalyst slurry and the second catalyst slurry each contained SiO as a filler. ２ The fuel production apparatus shown in Fig. 5 was produced in the same manner as in Example 1, except that particles were further added. ２ The particle addition rate was 20 parts by mass relative to 100 parts by mass of the first catalyst, and the SiO ２ The addition rate of the particles was 20 parts by mass relative to 100 parts by mass of the second catalyst. ２ The thermal conductivity of the particles is 1.38 W / m K, and SiO ２ The average particle size of the particles is 20 nm, and SiO ２ The aspect ratio of the particles was 1.0.

[0087] Example 3 The first catalyst slurry and the second catalyst slurry each contained α-Al as a filler. ２ O ３ The fuel production apparatus shown in Fig. 5 was produced in the same manner as in Example 1, except that particles were further added. ２ O３ The addition rate of the particles was 20 parts by mass relative to 100 parts by mass of the first catalyst, and the α-Al ２ O ３ The addition rate of the particles was 20 parts by mass relative to 100 parts by mass of the second catalyst. ２ O ３ The thermal conductivity of the particles is 30 W / m·K, and the α-Al ２ O ３ The average particle size of the particles is 400 nm, and the α-Al ２ O ３ The aspect ratio of the particles was 10.

[0088] Example 4 Preparation of Honeycomb Substrate A honeycomb substrate was prepared in the same manner as in Example 1.

[0089] <<Preparation of First Catalyst Layer>> Triiron tetroxide (Fe ３ O ４ ) particles were dispersed in distilled water to prepare a first catalyst slurry. The catalyst particle content in the first catalyst slurry was 10 mass%. Next, the first catalyst slurry was flowed into a plurality of first cells provided in the honeycomb substrate prepared above under normal pressure (0.1 MPa) and room temperature (23°C). In this way, the first catalyst slurry was applied to the surfaces of the partition walls. Thereafter, the first catalyst slurry applied to the surfaces of the partition walls was heated and dried at 100°C for 120 minutes. The above application and drying were repeated to form a first catalyst layer on the surfaces of the partition walls. The thickness of the first catalyst layer was 40 μm. The amount of the first catalyst particles supported per unit area of ​​the partition walls was 0.011 g / cm ２ It was.

[0090] <<Preparation of Second Catalyst Layer>> Commercially available HZSM-5 (zeolite, manufactured by Nakamura Choukou Co., Ltd.) was calcined in an electric furnace at 500°C for 4 hours to obtain second catalyst particles. The obtained second catalyst particles were dispersed in distilled water to prepare a second catalyst slurry. The catalyst particle content in the second catalyst slurry was 10 mass%. Next, the second catalyst slurry was flowed into the multiple second cells of the honeycomb substrate prepared above at normal pressure (0.1 MPa) and room temperature (23°C). In this way, the second catalyst slurry was applied to the surface of the partition wall on the second flow path side. Thereafter, the second catalyst slurry applied to the surface of the partition wall was heated and dried at 100°C for 120 minutes. The above-mentioned application 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 80 μm. The amount of second catalyst particles loaded per unit area of ​​the partition wall was 0.011 g / cm. ２ In this way, the fuel production device shown in FIG. 6 was manufactured.

[0091] Example 5 A fuel production apparatus shown in FIG. 6 was produced in the same manner as in Example 4, except that the first catalyst slurry containing triiron tetroxide particles was changed to the first catalyst slurry used in Example 1.

[0092] Example 6 A fuel production apparatus shown in Fig. 5 was manufactured in the same manner as in Example 1, except that the clay containing the SiC raw material powder and the metal Si powder was changed to a clay containing cordierite (Cd). In the honeycomb substrate of Example 6, the partition wall thickness was 0.254 mm, the average pore diameter of the partition walls was 11 µm, and the porosity of the partition walls was 52%.

[0093] Example 7 A fuel production apparatus shown in Fig. 6 was manufactured in the same manner as in Example 5, except that the clay containing the SiC raw material powder and the metal Si powder was changed to a clay containing cordierite (Cd). In the honeycomb substrate of Example 7, the partition wall thickness was 0.254 mm, the average pore diameter of the partition walls was 11 µm, and the porosity of the partition walls was 52%.

[0094] Example 8 A honeycomb substrate having partition walls functioning as a second catalyst layer was prepared in the same manner as in Example 1, except that the clay containing the SiC raw material powder and the metal Si powder was replaced with a clay containing HZSM-5 (zeolite, manufactured by Nakamura Choukou Co., Ltd.) as the second catalyst. In this honeycomb substrate, the partition wall thickness was 0.254 mm, the average pore diameter of the partition walls was 3 μm, and the porosity of the partition walls was 40%. Next, a first catalyst slurry prepared in the same manner as in Example 1 was flowed into a plurality of first cells provided in the honeycomb substrate prepared above at normal pressure (0.1 MPa) and room temperature (23°C). This resulted in the first catalyst slurry being coated on the surface of the partition walls (second catalyst layer). The first catalyst slurry coated on the surface of the partition walls was then heated and dried at 100°C for 120 minutes. The above-described coating and drying processes were repeated to form a first catalyst layer on the surface of the partition walls. The thickness of the first catalyst layer was 80 μm. The amount of the first catalyst particles supported per unit area of ​​the partition wall was 0.011 g / cm. ２ In this way, the fuel production device shown in FIG. 7 was manufactured.

[0095] Comparative Example 1: In the same manner as in Example 1 described in JP 2017-144426 A, β zeolite-Co / Al ２ O ３ A catalyst was prepared. The catalyst was a Co / Al ２ O ３ The reaction tube was covered with quartz wool on both sides, and the resulting β zeolite-Co / Al membrane was used as the core and shell, respectively. ２ O ３ The catalyst was packed between the quartz wool in the same amount as in Example 1. In this way, a fuel production device was manufactured in which the catalyst having a core-shell structure was packed in the gas flow passage.

[0096] <Synthetic fuel production test> The fuel production apparatus obtained in the examples and comparative examples was inserted into a reaction tube with an inner diameter of 21 mm. As a pretreatment for the reaction, the fuel production apparatus was heated to 240°C using an electric furnace installed around 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 lower the temperature of the electric furnace to 200°C, and then a raw material gas containing 33 mol% carbon monoxide and 66 mol% hydrogen was introduced at a space velocity SV of 1018 h. －１ The raw material gas was introduced into the reaction tube at a rate of 1000 kJ / min. As a result, the raw material gas was supplied to the first flow path provided in the fuel production apparatus, and synthetic fuel gas flowed out from the reaction tube. The internal pressure of the first flow path was 1 MPa. In addition, the composition of the synthetic fuel gas flowing out from the reaction tube after the heating of the electric furnace was stopped was measured using a gas chromatograph-thermal conductivity detector (GC-TCD). Based on the measurement results, the conversion rate (%) of carbon monoxide to hydrocarbon compounds was calculated using the following formula (A). CO conversion rate (%) = (amount of hydrocarbon compounds contained in synthetic fuel gas (vol %) / sum of amount of hydrocarbon compounds and amount of carbon monoxide contained in synthetic fuel gas (vol %)) × 100 (A) In addition, the CH ４ The selectivity (%) was calculated by the following formula (B): CH ４Selectivity (%) = (amount of methane contained in synthetic fuel gas (vol %) / sum of amounts of hydrocarbon compounds and carbon oxides contained in synthetic fuel gas (vol %)) × 100 (B) C2 to C4 selectivity (%) was calculated using the following formula (C): C2 to C4 selectivity (%) = (sum of C2 to C4 hydrocarbon compounds contained in synthetic fuel gas (vol %) / sum of amounts of hydrocarbon compounds and carbon oxides contained in synthetic fuel gas (vol %)) × 100 (C) C5 to C20 selectivity (%) was calculated using the following formula (D): C5 to C20 selectivity (%) = (sum of C5 to C20 hydrocarbon compounds contained in synthetic fuel gas (vol %) / sum of amounts of hydrocarbon compounds and carbon oxides contained in synthetic fuel gas (vol %)) × 100 (D) C20+ selectivity (%) was calculated using the following formula (E). C20+selectivity (%) = (total amount of hydrocarbon compounds exceeding C20 contained in synthetic fuel gas (vol %) / total amount of hydrocarbon compounds and carbon oxides contained in synthetic fuel gas (vol %)) × 100 (E) Isoparaffin selectivity (%) was calculated using the following formula (F): Isoparaffin selectivity (%) = (total amount of isoparaffin compounds contained in synthetic fuel gas (vol %) / total amount of hydrocarbon compounds and carbon oxides contained in synthetic fuel gas (vol %)) × 100 (F) Olefin selectivity (%) was calculated using the following formula (G): Olefin selectivity (%) = (total amount of olefin compounds contained in synthetic fuel gas (vol %) / total amount of hydrocarbon compounds and carbon oxides contained in synthetic fuel gas (vol %)) × 100 (G) C5 to C20 yield (%) was calculated using the following formula (H). C5 to C20 yield (%) = (CO conversion (%) (A)) × (C5 to C20 selectivity (%) (D)) × 100 (H) Furthermore, the isoparaffin yield (%) was calculated using the following formula (I): Isoparaffin yield (%) = (CO conversion (%) (A)) × (isoparaffin selectivity (%) (F)) × 100 (I) Furthermore, the olefin yield (%) was calculated using the following formula (J): Olefin yield (%) = (CO conversion (%) (A)) × (olefin selectivity (%) (G)) × 100 (J) These results are shown in Table 1.

[0097]

[0098] <Evaluation> As shown in Table 1, when the second catalyst layer containing the second catalyst capable of promoting the hydrocracking reaction and / or the isomerization reaction of hydrocarbon compounds is located on the opposite side of the first flow path with respect to the first catalyst layer containing the first catalyst capable of promoting the Fischer-Tropsch reaction, it is possible to improve the carbon oxide conversion rate and efficiently produce synthetic fuel, compared to the case where the gas flow path is filled with a catalyst having a core-shell structure (Comparative Example 1).

[0099] The fuel production apparatus according to the embodiment of the present invention can be used to produce synthetic fuels, and can be particularly suitably used to produce hydrocarbon-based synthetic fuels having 5 to 12 carbon atoms.

[0100] REFERENCE SIGNS LIST 1 First catalyst layer 2 Second catalyst layer 3 Substrate 3c Honeycomb substrate 31 Partition wall 4 First flow path 5 Second flow path 6 First plugging portion 7 Second plugging portion 10 Honeycomb structure 11 Honeycomb structure 100 Fuel production device 101 Fuel production device 102 Fuel production device

Claims

1. A fuel production apparatus comprising: a first flow path to which a feed gas containing carbon oxides and hydrogen is supplied; a first catalyst layer disposed facing the first flow path, the first catalyst layer including a first catalyst capable of promoting a Fischer-Tropsch reaction; and a second catalyst layer disposed on the opposite side of the first flow path from the first catalyst layer, the second catalyst layer including a second catalyst capable of promoting a hydrocracking reaction and / or an isomerization reaction of a hydrocarbon compound produced by the Fischer-Tropsch reaction.

2. The fuel production device according to claim 1, further comprising a second flow path located on the opposite side of the second catalyst layer from the first catalyst layer, through which a synthetic fuel produced by a hydrocracking reaction and / or an isomerization reaction of the hydrocarbon compound flows.

3. The fuel production apparatus according to claim 2, comprising a honeycomb structure having a plurality of first cells including said first flow passages and a plurality of second cells including said second flow passages.

4. A fuel production device as described in claim 3, wherein each of the plurality of first cells and the plurality of second cells extends from a first end face to a second end face of the honeycomb structure, and the honeycomb structure is provided with first sealing portions provided on at least a portion of the plurality of first cells, the first sealing portions sealing the ends of the first flow paths on the second end face side.

5. A fuel production device as described in claim 4, wherein the honeycomb structure is provided with second plugging portions provided in at least a portion of the plurality of second cells, the second plugging portions sealing the ends of the second flow paths on the first end face side.

6. The fuel production device according to claim 3, wherein the honeycomb structure comprises a honeycomb substrate having partition walls that define the plurality of first cells and the plurality of second cells, the second catalyst layer is laminated on the surface of the partition walls that faces the first flow path, and the first catalyst layer is located on the opposite side of the partition walls with respect to the second catalyst layer and is laminated on the second catalyst layer.

7. The fuel production apparatus according to claim 6, wherein the porosity of the partition wall is 25% to 70%.

8. The fuel production apparatus according to claim 6, wherein the thermal conductivity of the partition wall is 0.4 W / mK or more.

9. The fuel production apparatus according to claim 8, wherein the thermal conductivity of the partition wall is 8 W / mK or more.

10. The fuel production apparatus of claim 8, wherein the partition wall comprises cordierite and / or SiC.

11. The fuel production apparatus of claim 9, wherein the partition wall comprises SiC.

12. The fuel production apparatus according to any one of claims 1 to 11, wherein the first catalyst contains at least one transition metal.

13. The fuel production apparatus of claim 12, wherein the transition metal comprises Co and / or Fe.

14. A fuel production apparatus according to any one of claims 1 to 11, wherein the second catalyst includes a zeolite.

15. A fuel production device according to any one of claims 1 to 11, wherein the first catalyst layer and / or the second catalyst layer further contains a filler, and the thermal conductivity of the filler is 0.1 W / m·K to 500 W / m·K.

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