Method and reactor for capturing solid carbon

Abstract

To capture solid carbon with high efficiency from gases containing carbon monoxide and hydrogen. [Solution] A method for capturing solid carbon includes: preparing a reactor having a solid carbon capture reactor and a solid carbon capture catalyst body, including multiple solid carbon capture units and a trap unit for trapping moisture, and a gas flow path including the solid carbon capture reactor and the trap unit; and supplying a source gas containing carbon monoxide and hydrogen to the gas flow path while heating the solid carbon capture catalyst body, thereby depositing solid carbon on the solid carbon capture catalyst body. The trap unit is disposed between two adjacent solid carbon capture units in the gas flow path. The solid carbon capture catalyst body has a catalyst layer containing a metal oxide including Fe and a non-ferrous metal, and the non-ferrous metal is one or more selected from a group including Co, etc.

Description

[Technical Field]

[0001] The present disclosure relates to a method and reactor for capturing solid carbon. [Background technology]

[0002] Patent Document 1 discloses a catalyst that enables efficient capture of solid carbon at relatively low temperatures, and a solid carbon capture device equipped with the catalyst. Patent Document 2 discloses a method for producing a forest of fibrous solid carbon. Non-Patent Document 1 discloses a method for CVD synthesis of carbon nanotubes. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2021 / 235443 [Patent Document 2] Special Publication No. 2019-528223 [Non-patent literature]

[0004] [Non-Patent Document 1] Z Balogh et al, Applied Catalysis A: General, 344,1-2,15, July.2008 Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure relates to the highly efficient capture of solid carbon from gases containing carbon monoxide and hydrogen. [Means for solving the problem]

[0006] The present disclosure includes the following: [1] preparing a reaction apparatus having a solid carbon capture reactor and a solid carbon capture catalyst body, wherein the solid carbon capture catalyst body is provided in the solid carbon capture reactor, or the solid carbon capture catalyst body also serves as the solid carbon capture reactor, the reaction apparatus comprising a plurality of solid carbon capture units and a trap unit for trapping moisture, and a gas flow path including the solid carbon capture reactor and the trap unit; supplying a raw material gas containing carbon monoxide and hydrogen to the gas flow passage while heating the solid carbon capture catalyst body, thereby depositing solid carbon on the solid carbon capture catalyst body; 1. A method for capturing solid carbon, comprising: A plurality of the solid carbon traps are connected in series along the gas flow path, and the trap unit is disposed between two adjacent solid carbon traps on the gas flow path; The method, wherein the solid carbon capture catalyst body has a catalyst layer containing a metal oxide containing Fe and a non-ferrous metal, and the non-ferrous metal is one or more selected from the group consisting of Co, Mg, Ni, Mn, Mo, K, Na, Li, Ca, Cs, Sr, Ba, La, Ce, Pd, Nd, Cu, and Zn. [2] The method according to [1], wherein the pressure in the gas flow path to which the source gas is supplied exceeds atmospheric pressure. [3] the reaction apparatus further comprises a reverse water gas shift reaction section having a reverse water gas shift reaction reactor and a reverse water gas shift reaction catalyst provided in the reverse water gas shift reaction reactor; the gas flow path further comprises a reactor for the reverse water gas shift reaction; the reverse water gas shift reactor is disposed between two adjacent solid carbon capture units in the gas flow path; The method according to [1] or [2], wherein the reactor comprises the trapping unit disposed between the reverse water gas shift reactor and the solid carbon trapping unit located upstream in the gas flow path, and the trapping unit disposed between the reverse water gas shift reactor and the solid carbon trapping unit located downstream in the gas flow path. [4] The method according to [3], wherein the reverse water gas shift reaction catalyst has a catalyst layer containing a metal oxide containing Cu and Zn. [5] the reaction device further comprises a dry reforming section having a dry reforming reactor and a dry reforming catalyst body provided in the dry reforming reactor, the dry reforming section being connected to the solid carbon capture section located most upstream in the gas flow path, The method according to any one of [1] to [4], wherein a gas containing methane and carbon dioxide is supplied to the dry reforming unit, and a gas containing carbon monoxide and hydrogen discharged from the dry reforming unit is supplied as the raw material gas to the gas flow path including the solid carbon capture unit. [6] the reaction apparatus further comprises a methanation unit having a methanation reactor and a methanation catalyst body provided in the methanation reactor and connected to the dry reforming unit; The method according to [5], wherein a gas containing carbon dioxide and hydrogen is supplied to the methanation unit, and a gas containing methane and carbon dioxide discharged from the methanation unit is supplied to the dry reforming unit. [7] The method according to any one of [1] to [6], wherein the raw material gas is supplied to the gas flow channel while the solid carbon capture catalyst body is heated to 500° C. or less. [8] The method according to any one of [1] to [7], wherein the proportion of the non-ferrous metal in the catalyst layer is 40 mol % or more with respect to the total amount of the Fe and the non-ferrous metal. [9] a plurality of solid carbon capture units each having a solid carbon capture reactor and a solid carbon capture catalyst body, the solid carbon capture catalyst body being provided in the solid carbon capture reactor, or the solid carbon capture catalyst body also serving as the solid carbon capture reactor; a trap portion that traps moisture; Equipped with a gas flow path including the solid carbon capture reactor and the trap section is formed; A plurality of the solid carbon trapping units are arranged in series along the gas flow path, and the trap unit is arranged between two adjacent solid carbon trapping units on the gas flow path, a reactor, wherein the solid carbon capture catalyst body has a catalyst layer containing a metal oxide containing Fe and a non-ferrous metal, and the non-ferrous metal is one or more selected from the group consisting of Co, Mg, Ni, Mn, Mo, K, Na, Li, Ca, Cs, Sr, Ba, La, Ce, Pd, Nd, Cu, and Zn.

[10] the reaction apparatus further comprises a reverse water gas shift reaction section having a reverse water gas shift reaction reactor and a reverse water gas shift reaction catalyst provided in the reverse water gas shift reaction reactor; the gas flow path further comprises a reactor for the reverse water gas shift reaction; the reverse water gas shift reactor is disposed between two adjacent solid carbon capture units in the gas flow path; The reaction apparatus according to [9], further comprising: the trap unit disposed between the reverse water gas shift reaction unit and the solid carbon capture unit located upstream in the gas flow path; and the trap unit disposed between the reverse water gas shift reaction unit and the solid carbon capture unit located downstream in the gas flow path.

[11] The reaction device according to

[10] , wherein the reverse water gas shift reaction catalyst comprises a metal oxide containing Cu and Zn.

[12] The reaction apparatus according to any one of [9] to

[11] , further comprising a dry reforming unit that has a dry reforming reactor and a dry reforming catalyst body provided in the dry reforming reactor, and that is connected to the solid carbon capture unit that is located most upstream in the gas flow path.

[13] The reaction apparatus according to

[12] , further comprising a methanation unit having a methanation reactor and a methanation catalyst body provided in the methanation reactor, and connected to the dry reforming unit.

[14] The reaction apparatus according to any one of [9] to

[13] , wherein the proportion of the non-ferrous metal in the catalyst layer is 40 mol % or more with respect to the total amount of the Fe and the non-ferrous metal. [Effects of the Invention]

[0007] Solid carbon can be collected with high efficiency from gases containing carbon monoxide and hydrogen. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram showing an example of a reactor for solid carbon capture. [Figure 2] FIG. 2 is a cross-sectional view showing an example of a solid carbon capture catalyst body. [Figure 3] FIG. 2 is a cross-sectional view showing an example of a solid carbon capture catalyst body. [Figure 4] FIG. 1 is a schematic diagram showing an example of a reactor for solid carbon capture. [Figure 5] FIG. 1 is a schematic diagram showing an example of a reactor for solid carbon capture. [Figure 6] 1 is a graph showing the amount of solid carbon collected in Example 1 and Comparative Example 1. [Figure 7] 1 is a graph showing the carbon capture efficiency in the solid carbon capture section of Examples 2B to 2F and Comparative Examples 2A to 2C. [Figure 8] 1 is a graph showing the relationship between carbon capture efficiency and temperature in Example 5A or Example 5B. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present invention is not limited to the following examples.

[0010] Fig. 1 is a schematic diagram showing an example of a reaction apparatus used to capture solid carbon. The reaction apparatus 101 shown in Fig. 1 includes a plurality of solid carbon capture units 11, 12, and 13, a plurality of trap units 20a, 20b, 20c, and 20d for trapping moisture, a dry reforming unit 40, and a plurality of pipes 60a, 60b, 60c, 60d, 60e, 60f, 60g, 60h, and 60i. The reaction apparatus 101 further includes a heater 8 for heating the solid carbon capture units 11, 12, and 13 or the dry reforming unit 40. The dry reforming unit 40 does not necessarily have to be provided.

[0011] The reactor 101 is a multi-stage flow reactor including multiple carbon capture reactors connected via pipes and traps arranged between the multiple reactors. Each of the multiple solid carbon capture reactors 11, 12, and 13 includes a solid carbon capture reactor 6 and a solid carbon capture catalyst body 5 provided in the solid carbon capture reactor 6. The dry reforming unit 40 includes a dry reforming reactor 41 and a dry reforming catalyst body 42 provided in the dry reforming reactor 41. The reactor 101 has a gas flow path including the dry reforming reactor 41, the solid carbon capture reactor 6, and traps 20a to 20d. In other words, within the reactor 101, gas can flow along the gas flow path, passing through the dry reforming reactor 41, the solid carbon capture reactor 6, and the traps 20a to 20d. The multiple solid carbon traps include a first-stage solid carbon trap 11, a second-stage solid carbon trap 12, and a third-stage solid carbon trap 13, which are arranged in series from the upstream side along the gas flow path. The number of solid carbon traps constituting the reactor is two or more. The greater the number of solid carbon traps, the higher the efficiency of solid carbon capture in the entire reactor. Since the solid carbon capture rate in the downstream solid carbon traps tends to be relatively lower, the number of solid carbon traps may be four or less from the perspective of efficient carbon capture.

[0012] The multiple trap sections include trap section 20b arranged between the first-stage solid carbon trap section 11 and the second-stage solid carbon trap section 12 that are adjacent to each other in the gas flow path, and trap section 20c arranged between the second-stage solid carbon trap section 12 and the third-stage solid carbon trap section 13 that are adjacent to each other in the gas flow path. In the example of Figure 1, the multiple trap sections further include trap section 20a arranged upstream of the first-stage solid carbon trap section 11 that is located most upstream in the gas flow path among the multiple solid carbon trap sections, and trap section 20d arranged downstream of the third-stage solid carbon trap section 13 that is located most downstream in the gas flow path among the multiple solid carbon trap sections.

[0013] The pipes constituting the reaction apparatus connect the dry reforming reactor, the solid carbon capture reactor, and the trap unit so as to form a gas flow path including the dry reforming reactor, the solid carbon capture reactor, and the trap unit. In the example of Fig. 1, the multiple pipes include a pipe 60a connected to the gas inlet of the dry reforming reactor 41, a pipe 60b connecting the dry reforming reactor 41 and the trap unit 20a, a pipe 60c connecting the trap unit 20a and the solid carbon capture reactor 6 of the first-stage solid carbon capture unit 11, a pipe 60d connecting the solid carbon capture reactor 6 of the first-stage solid carbon capture unit 11 and the trap unit 20b, and a pipe 60e connecting the trap unit 20b and the second-stage solid carbon capture unit 11. The solid carbon trapping reactor 6 of the third-stage solid carbon trapping unit 13 includes a pipe 60e connecting the second solid carbon trapping reactor 6 to the second solid carbon trapping unit 12, a pipe 60f connecting the trap unit 20c to the second solid carbon trapping reactor 6 of the second solid carbon trapping unit 12, a pipe 60g connecting the trap unit 20c to the second solid carbon trapping reactor 6 of the third-stage solid carbon trapping unit 13, a pipe 60h connecting the second solid carbon trapping reactor 6 of the second solid carbon trapping unit 12 to the trap unit 20d, and a pipe 60i connected to the trap unit 20d. Normal equipment such as valves and pressure gauges may be provided on each pipe as necessary.

[0014] A method for capturing solid carbon using the reaction device 101 includes, for example, supplying a source gas G0 containing carbon monoxide and hydrogen to the gas flow passage while heating the solid carbon capture catalyst body 5 with a heater 8, thereby depositing solid carbon on the solid carbon capture catalyst body 5 in the solid carbon capture reactor 6. The solid carbon is deposited mainly on the surface of the solid carbon capture catalyst body 5.

[0015] In the capture of solid carbon from gases containing carbon monoxide and hydrogen, the CO reduction reaction and the Boudouard reaction are generally considered to be involved in the precipitation of solid carbon. Therefore, when solid carbon is captured in multiple solid carbon capture units, providing a trap for trapping moisture produced by the CO reduction reaction is expected to further promote the precipitation of solid carbon in the downstream solid carbon capture unit. However, as confirmed in the Examples described below, when the catalyst for solid carbon capture is an oxide of a single metal such as Fe, the introduction of a trap does not significantly promote solid carbon capture. However, when a metal oxide containing a combination of Fe and a specific non-ferrous metal is used as the catalyst, the introduction of a trap significantly promotes the capture of solid carbon in the downstream solid carbon capture unit. This is thought to be because metal oxides containing Fe and non-ferrous metals promote the reverse water-gas shift reaction, which is also a reaction that produces moisture. The reverse water-gas shift reaction converts the CO2 produced in the Boudouard reaction back to CO, thereby accelerating the Boudouard reaction and improving the efficiency of solid carbon capture. CO+H2→C+H2O (CO reduction reaction) CO+CO→C+CO2 (Boudouard reaction) CO2 + H2 → CO + H2O (reverse water gas shift reaction)

[0016] Fig. 2 is a cross-sectional view showing an example of a catalyst body for solid carbon capture. The catalyst body 5 for solid carbon capture shown in Fig. 2 is a hollow structure having a tubular substrate 1 and a catalyst layer 3 formed on the inner wall surface of the substrate 1. Fig. 3 is a plan view and a cross-sectional view showing another example of a catalyst body for solid carbon capture. The catalyst body 5 for solid carbon capture shown in Fig. 3 is a structure having a substrate 1 that is a plate-like body extending along the axis X while twisting in the direction of rotation about the axis X, and a catalyst layer 3 formed on the surface of the substrate 1. The shape of the substrate 1 shown in Fig. 3 is sometimes called a spiral type.

[0017] The substrate 1 may be a metal molded body, such as a stainless steel or aluminum material. When the substrate 1 is a tubular body having a circular inner wall surface, its inner diameter is not particularly limited and may be, for example, 10 to 300 mm or 10 to 1000 mm. The length of the substrate 1 is not particularly limited and may be, for example, 20 to 5000 mm. The substrate 1 is not limited to a linear tubular body as shown in the example of FIG. 1 or a spiral-shaped plate as shown in the example of FIG. 2. For example, the substrate of the catalyst body may be a twisted tubular body, a hollow structure other than a tubular body, or a bent tubular or plate-like body. A plurality of structures of these shapes may be stacked or joined together. When the substrate 1 is a tubular body or another hollow structure, the solid carbon capture catalyst body may also serve as a solid carbon capture reactor without providing a solid carbon capture reactor separately from the solid carbon capture catalyst body.

[0018] The catalytic layer 3 contains a metal oxide containing Fe and a non-ferrous metal as a catalytically active component. The non-ferrous metal may be one or more selected from the group consisting of Co, Mg, Ni, Mn, Mo, K, Na, Li, Ca, Cs, Sr, Ba, La, Ce, Pd, Nd, Cu, and Zn. The metal oxide contained in the catalytic layer 3 may be a composite oxide containing Fe and a non-ferrous metal. A catalytic layer containing a combination of Fe and a specific non-ferrous metal, when combined with a moisture trap, can specifically and efficiently precipitate solid carbon from a gas containing carbon monoxide and hydrogen.

[0019] The non-ferrous metal may include one or more selected from the group consisting of Co, Ni, K, Na, Li, Cu, and Zn. The non-ferrous metal may include Co, Ni, or both. The non-ferrous metal may include Co, Ni, or both, and one or more selected from K, Na, Li, Cu, and Zn.

[0020] The proportion of non-ferrous metals in the catalyst layer 3 can be adjusted depending on the type of non-ferrous metal, etc. A high proportion of non-ferrous metals tends to enable more efficient capture of solid carbon by the combination of the solid carbon capture section and the trap section. From this perspective, the proportion of non-ferrous metals may be 40 mol% or more, 50 mol% or more, more than 50 mol%, 60 mol% or more, or 70 mol% or more, or may be 95 mol% or less, or 90 mol% or less, based on the total amount of Fe and non-ferrous metals.

[0021] The proportion of the metal oxide containing Fe and a non-ferrous metal in the catalytic layer 3 may be 40 to 100 mass%, 50 to 100 mass%, 60 to 100 mass%, 70 to 100 mass%, 80 to 100 mass%, or 90 to 100 mass% based on the mass of the catalytic layer 3. The catalytic layer 3 may include a support containing aluminum oxide (Al2O3) and a metal oxide supported on the support.

[0022] The catalyst layer 3 is formed so as to cover the entire or part of the surface (for example, the inner wall surface) of the substrate 1. The thickness of the catalyst layer 3 is not particularly limited, but may be, for example, 5 to 2000 μm, or 10 to 2000 μm. The catalyst layer 3 may be porous.

[0023] The catalyst layer 3 can be formed, for example, by a method including removing water from an aqueous solution containing iron ions and non-ferrous metal ions to obtain a powder, calcining the powder to obtain catalyst particles containing metal oxides including iron and non-ferrous metals, forming a catalyst slurry containing the catalyst particles and a dispersion medium, depositing the catalyst slurry on the surface of the substrate 1, and removing the dispersion medium from the catalyst slurry deposited on the surface of the substrate 1. The dispersion medium of the catalyst slurry may be, for example, water, alcohol, acetone, or a combination thereof.

[0024] The dry reforming reactor and the solid carbon capture reactor may be hollow structures through which gas can flow and which can accommodate the dry reforming catalyst body or the solid carbon capture catalyst body. The dry reforming reactor and the solid carbon capture reactor may also be tubular bodies.

[0025] The solid carbon capture catalyst body 5 is inserted into the solid carbon capture reactor 6. A plurality of solid carbon capture catalyst bodies 5 may be arranged in series along the longitudinal direction of the solid carbon capture reactor 6. The number of solid carbon capture catalyst bodies 5 provided in one solid carbon capture reactor 6 can be appropriately determined based on factors such as the ease of handling for forming the catalyst layer and collecting the deposited solid carbon. For example, the number of solid carbon capture catalyst bodies 5 provided in one solid carbon capture reactor 6 may be 1 or more and 10 or less. The solid carbon capture reactor 6 may be a tubular body having an inner diameter larger than the outer diameter of the solid carbon capture catalyst body 5.

[0026] The heater 8 is not limited as long as it is a device that can heat the solid carbon capture catalyst body 5 in the solid carbon capture reactor 6. The heater 8 may be an electric furnace, and one or more solid carbon capture reactors may be disposed in the electric furnace that serves as the heater 8. The heater may be wrapped around the solid carbon capture reactor 6.

[0027] The temperature to which the solid carbon capture catalyst body 5 is heated to precipitate solid carbon may be, for example, 800° C. or less, 700° C. or less, 650° C. or less, 550° C. or less, or 500° C. or less. According to the method according to the present disclosure, solid carbon can be efficiently captured even at a relatively low temperature. The temperature to which the solid carbon capture catalyst body 5 is heated to precipitate solid carbon may be 300°C or higher and 800°C or lower, 700°C or lower, 650°C or lower, 550°C or lower, or 500°C or lower, or 330°C or higher and 800°C or lower, 700°C or lower, 650°C or lower, 550°C or lower, or 500°C or higher, or 350°C or higher and 800°C or lower, 700°C or lower, 650°C or lower, 550°C or lower, or 500°C or higher, or 380°C or higher and 800°C or lower, 700°C or lower, 650°C or lower, 550°C or lower, or 500°C or lower.

[0028] Each of the traps 20a to 20d can be any device capable of trapping moisture in the gas flowing through the gas flow path. The trap may be, for example, a cooling trap that condenses water vapor by cooling using a cooling gas or a cooling liquid. The trap may also be a trap containing a porous material such as zeolite that can selectively adsorb and remove moisture.

[0029] In the solid carbon capture method according to the present disclosure, pressurization of the gas flow path including the solid carbon capture reactor can also be effective. In the case of a single-stage reactor equipped with one reactor, pressurization tends to reduce capture efficiency. However, the effect of pressurization can be particularly pronounced when multiple reactors are connected to form a multi-stage reactor, in combination with a trap section that traps moisture. From this perspective, the pressure of the gas flowing through the gas flow path to which the source gas G0 is supplied may be higher than atmospheric pressure. For example, by supplying a pressurized source gas G0 and maintaining the pressure in the gas flow path using a pressure control valve or the like, a gas having a pressure higher than atmospheric pressure can be circulated through the gas flow path. High pressure gas flowing through the gas flow path can further improve the efficiency of solid carbon capture. The pressure in the gas flow path may be 0.20 MPa or higher, 0.30 MPa or higher, 0.40 MPa or higher, 0.50 MPa or higher, 0.60 MPa or higher, 0.70 MPa or higher, 0.8 MPa or higher, or 1.0 MPa or higher. If the gas pressure in the gas flow passage is high, the energy efficiency may decrease, so the gas pressure in the gas flow passage may be 2.0 MPa or less.

[0030] After solid carbon is precipitated, the supply of the raw material gas G0 is stopped, and the solid carbon capture catalyst body 5 is removed from the solid carbon capture reactor 6, allowing the solid carbon to be collected. When the solid carbon capture catalyst body also serves as a solid carbon capture reactor, solid carbon can be directly collected from the solid carbon capture catalyst body serving as a solid carbon capture reactor. The time period for which the raw material gas G0 is supplied in one solid carbon capture is not particularly limited and can be adjusted according to the amount of raw material gas, the capacity of the solid carbon capture catalyst body 5, and the like. Additionally, the time period for which the raw material gas G0 is supplied is adjusted taking into consideration the time required to capture solid carbon and the operating efficiency of the reactor. For example, the time period for which the raw material gas G0 is supplied in one solid carbon capture may be 5 hours or more and 10 hours or less. Solid carbon collection may be performed by daily start-stop operation. Solid carbon can also be continuously captured and collected without stopping the supply of the raw material gas G0 by switching the solid carbon capture reactor 6 in a cartridge-type rotation.

[0031] A gas containing methane and carbon dioxide may be supplied to the dry reforming section 40, and a gas containing carbon monoxide and hydrogen discharged from the dry reforming section 40 may be supplied as raw material gas G0 to a gas flow passage downstream of the dry reforming section 40. The dry reforming catalyst body 42 of the dry reforming section 40 may be a structure having a catalyst layer containing a dry reforming catalyst that promotes the following dry reforming reaction. The dry reforming catalyst body 42 may have a substrate having any shape and a catalyst layer provided on the substrate. CH4 + CO2 → 2CO + 2H2 (dry reforming reaction)

[0032] The dry reforming catalyst may be, for example, Ni, Co, Mo, Rh, Ru, Al, Zr, Mg, or an oxide thereof. A gas containing methane and carbon dioxide may be supplied to the dry reforming section 40 while the dry reforming catalyst body 42 is heated by the heater 8. In this case, the heating temperature may be, for example, 550°C or higher and 700°C or lower.

[0033] FIG. 4 is also a schematic diagram showing an example of a reactor used to capture solid carbon. The reactor 102 shown in FIG. 4 includes a first-stage solid carbon capture section 11, a second-stage solid carbon capture section 12, and a reverse water-gas shift reactor 30 disposed therebetween. A trap section 20b is disposed between the first-stage solid carbon capture section 11 and the reverse water-gas shift reactor 30. A trap section 20c is disposed between the reverse water-gas shift reactor 30 and the second-stage solid carbon capture section 12. Otherwise, the reactor 102 has substantially the same configuration as the reactor 101. By providing a trap section 20c located downstream of the reverse water-gas shift reactor 30 in the gas flow path and a trap section 20c located downstream of the reverse water-gas shift reactor 30 in the gas flow path, solid carbon can be captured more efficiently. The trap section 20d is not necessarily provided. When three or more solid carbon traps are provided, a reverse water gas shift reaction section can be disposed between the two solid carbon traps in at least some of the combinations of two adjacent solid carbon traps in the gas flow path.

[0034] The reverse water gas shift reactor 30 includes a reverse water gas shift reactor 31 and a reverse water gas shift catalyst 32 disposed within the reverse water gas shift reactor 31. The reactor 102 includes a gas flow path including a dry reforming reactor 41, a solid carbon capture reactor 6, the reverse water gas shift reactor 31, and traps 20a-20d. The reverse water gas shift catalyst 32 may be a structure having a catalyst layer containing a reverse water gas shift catalyst that promotes the reverse water gas shift reaction. The reverse water gas shift catalyst 32 may include a substrate having any shape and a catalyst layer disposed on the substrate. The reverse water gas shift catalyst 32 may be a catalyst layer formed by packing a granular reverse water gas shift catalyst into the reverse water gas shift reactor 31. The reverse water gas shift catalyst may be a metal oxide containing Cu and Zn in terms of high catalytic activity. The reverse water gas shift reaction catalyst may be a metal oxide containing Cu and Zn and an additional metal selected from Co, Fe, etc. These metal oxides may be supported on a support containing alumina. Metal oxides supported on a support may exhibit higher performance. The reverse water gas shift reaction reactor may be a hollow structure that allows gas to flow through and can accommodate a reverse water gas shift reaction catalyst body. The reverse water gas shift reaction reactor may be a tubular body.

[0035] While the feed gas G0 is being supplied to the gas flow path for solid carbon capture, gas containing CO2 and other compounds produced by the Boudouard reaction flows into the reverse water-gas-shift reactor 30 from a solid carbon collector located upstream of the reverse water-gas-shift reactor 30. In the reverse water-gas-shift reactor 30, CO2 is converted to CO and water is produced by the reverse water-gas-shift reaction. By trapping water in the trap 20b located upstream of the reverse water-gas-shift reactor 30, the reverse water-gas-shift reaction is further accelerated in the reverse water-gas-shift reactor 30. As a result, solid carbon can be deposited more efficiently in the downstream solid carbon collector. While the feed gas G0 is being supplied to the gas flow path, the reverse water-gas-shift reactor catalyst 32 may be heated. In this case, the heating temperature may be the same as or higher than the heating temperature of the solid carbon capture catalyst 5.

[0036] Figure 5 is also a schematic diagram showing an example of a reactor used to capture solid carbon. The reactor 103 shown in Figure 5 includes a first-stage solid carbon collection section 11, a second-stage solid carbon collection section 12, multiple trap sections 20a, 20b, 20c, and 20d for trapping moisture, a dry reforming section 40, a methanation section 50, and multiple pipes 60a, 60b, 60c, 60d, 60e, 60f, 60g, 60h, and 60i. The reactor 103 further includes a heater 8 that heats the first-stage solid carbon collection section 11, the second-stage solid carbon collection section 12, the dry reforming section 40, or the methanation section 50. In the case of the reactor 103, the first-stage solid carbon collection section 11 and the second-stage solid carbon collection section 12 are heated by a single heater 8.

[0037] The methanation section 50 has a methanation reactor 51 and a methanation catalyst 52 provided in the methanation reactor 51. In the reactor 103, a gas flow path is formed including the methanation reactor 51, the dry reforming reactor 41, the solid carbon capture reactor 6, and trap sections 20a to 20d. The methanation section 50 is disposed upstream of the dry reforming section 40 in the gas flow path, and is connected to the dry reforming section 40 via a pipe 60a, the trap section 20a, and a pipe 60b. The methanation reactor may be a hollow structure that allows gas to flow through and that can accommodate a methanation catalyst. The methanation reactor may also be a tubular body.

[0038] The trap section 20a is arranged on the gas flow path between the methanation section 50 and the dry reforming section 40. The trap section 20b is arranged on the gas flow path between the dry reforming section 40 and the first-stage solid carbon collection section 11. The trap section 20c is arranged on the gas flow path between the first-stage solid carbon collection section 11 and the second-stage solid carbon collection section 12. The trap section 20d is arranged downstream of the second-stage solid carbon collection section 12. A drain trap 26 is further arranged between the trap section 20c and the second-stage solid carbon collection section 12. However, since the trap section 20c can also function as a drain trap, the drain trap 26 is not necessarily provided.

[0039] The piping constituting the reactor connects the methanation reactor, the dry reforming reactor, the solid carbon capture reactor, and the trap unit so as to form a gas flow path including the methanation reactor, the dry reforming reactor, the solid carbon capture reactor, and the trap unit. In the example of Figure 5, the multiple pipes include a pipe 60a connected to the gas inlet of the methanation reactor 51, a pipe 60b connecting the methanation reactor and the dry reforming reactor 41, a pipe 60c connecting the dry reforming reactor 41 and the trap section 20b, a pipe 60d connecting the trap section 20b and the solid carbon collection reactor 6 of the first-stage solid carbon collection section 11, a pipe 60e connecting the solid carbon collection reactor 6 of the first-stage solid carbon collection section 11 and the trap section 20c, a pipe 60f connecting the trap section 20c and the drain trap 26, a pipe 60g connecting the drain trap 26 and the solid carbon collection reactor 6 of the second-stage solid carbon collection section 12, a pipe 60h connecting the solid carbon collection reactor 6 of the second-stage solid carbon collection section 12 and the trap section 20d, and a pipe 60i connected to the trap section 20d. On each pipe, ordinary equipment such as a valve and a pressure gauge may be provided as necessary.

[0040] The methanation catalyst body 52 can be a structure having a catalyst layer containing a catalyst that promotes the following methanation reaction. The catalyst that promotes the methanation reaction can be arbitrarily selected from catalysts that are commonly used in methanation reactions. CO2 + 4H2 = CH4 + 2H2O (methanation reaction)

[0041] A method for capturing solid carbon using the reactor 103 includes, for example, supplying a gas containing carbon dioxide and hydrogen to the methanation unit 50, supplying the gas containing methane, unreacted carbon dioxide, and hydrogen discharged from the methanation unit 50 to the dry reforming unit 40, and supplying the raw material gas G0 containing carbon monoxide and hydrogen discharged from the dry reforming unit to a gas flow path including the solid carbon capture reactor 6 while heating the solid carbon capture catalyst 5 with a heater 8, thereby depositing solid carbon on the solid carbon capture catalyst in the solid carbon capture reactor 6. While supplying the gas containing carbon dioxide and hydrogen to the methanation unit 50, the methanation catalyst 52 and / or the dry reforming catalyst 42 may be heated as necessary. The gas supplied to the methanation unit 50 may be various exhaust gases containing carbon dioxide, etc.

[0042] [Example] The present invention is not limited to the following examples.

[0043] 1. Substrate Preparation A hollow stainless steel tubular body (outer diameter 20 mm × length 50 mm × thickness 1 mm, made of SUS304) was degreased by immersing it in a 3% by mass aqueous sodium hydroxide solution for 1 hour. The degreased tubular body was then washed with distilled water using an ultrasonic cleaner. The tubular body was then immersed in a 30% by volume aqueous hydrochloric acid solution for 1 hour, followed by thorough rinsing with distilled water to activate the inner wall surface of the tubular body. Finally, excess water was removed and the body was dried in air at 80°C to obtain a hollow tubular substrate.

[0044] 2. Preparation of solid carbon capture catalyst Catalyst #1 (Fe / Co) Iron(III) nitrate nonahydrate (Fe(NO3)3·9H2O, Fujifilm Wako Pure Chemical Industries, Ltd., 99%) and cobalt(II) nitrate hexahydrate (Co(NO3)2·6H2O, Wako Pure Chemical Industries, Ltd., 98%) were dissolved in 100 mL of distilled water at a molar ratio of 20:80 Fe:Co to obtain a metal nitrate mixed solution. The metal nitrate mixed solution was heated to 80-90°C on a hot plate while stirring, evaporating the water and obtaining a dry catalyst powder. The resulting dry catalyst powder was calcined in a tubular calcination furnace at 600°C for 3 hours while circulating dry air at 50 mL / min to obtain a catalyst particle powder containing a composite oxide containing Fe and Co in a molar ratio of 20:80. 2-Propanol was added to the resulting catalyst particle powder and stirred to obtain a catalyst slurry containing the catalyst particles. The substrate prepared in "1. Preparation of substrate" was immersed in this catalyst slurry for approximately 1 minute. Of the catalyst slurry adhering to the surface of the substrate, the portion adhering to the outer wall surface of the substrate was wiped off with a paper wipe. The catalyst slurry adhering to the inner wall surface of the substrate was dried with cold air from a dryer. By repeating this immersion and drying process, catalyst body #1 was obtained, which had a 120 mg catalyst layer formed on the inner wall surface of the hollow tubular substrate. The catalyst layer contained a catalyst containing a composite oxide containing Fe and Co.

[0045] Catalyst #2 (Fe / Ni) Iron(III) nitrate nonahydrate (Fe(NO3)3·9H2O, Fujifilm Wako Pure Chemical Industries, Ltd., 99%) and nickel(II) nitrate hexahydrate (Ni(NO3)2·6H2O, Fujifilm Wako Pure Chemical Industries, Ltd., 98%) were dissolved in 100 mL of distilled water at a molar ratio of 50:50 Fe:Ni to obtain a metal nitrate mixed solution. Catalyst #2 was prepared in the same manner as catalyst #1, except that this metal nitrate mixed solution was used. This catalyst layer contained a 120 mg catalyst layer formed on the inner wall surface of a hollow tubular substrate. The catalyst layer contained a catalyst containing a composite oxide containing Fe and Ni in a molar ratio of 50:50.

[0046] Catalyst #3 (Fe / Co / K) Iron(III) nitrate nonahydrate (Fe(NO3)3·9H2O, Fujifilm Wako Pure Chemical Industries, Ltd., 99%), cobalt(II) nitrate hexahydrate (Co(NO3)2·6H2O, Wako Pure Chemical Industries, Ltd., 98%), and potassium nitrate (KNO3, Fujifilm Wako Pure Chemical Industries, Ltd., 99%) were dissolved in 100 mL of distilled water in a molar ratio of 20:80:10 Fe:Co:K to prepare a metal nitrate mixed solution. Catalyst #3 was prepared in the same manner as catalyst #1, except that this metal nitrate mixed solution was used. The catalyst layer contained a catalyst containing a composite oxide containing Fe, Ni, and K in a molar ratio of 20:80:10.

[0047] Catalyst #4 (Fe / Co / Na) Catalyst #3 was obtained in the same manner as catalyst #3, except that potassium nitrate was replaced with sodium nitrate (NaNO, Fujifilm Wako Pure Chemical Industries, Ltd., 99%). The catalyst layer contained a catalyst containing a composite oxide containing Fe, Ni, and K in a molar ratio of 20:80:10.

[0048] Catalyst #5 (Fe / Co / Li) Catalyst #5 was obtained in the same manner as catalyst #3, except that potassium nitrate was replaced with lithium nitrate (LiNO3, Fujifilm Wako Pure Chemical Industries, Ltd., 99%). The catalyst layer contained a catalyst containing a composite oxide containing Fe, Ni, and Li in a molar ratio of 20:80:10.

[0049] Catalyst #6 (Fe / Co / Cu / Zn) Iron(III) nitrate nonahydrate (Fe(NO3)3·9H2O, Fujifilm Wako Pure Chemical Industries, Ltd., 99%), cobalt(II) nitrate hexahydrate (Co(NO3)2·6H2O, Fujifilm Wako Pure Chemical Industries, Ltd., 98%), copper(II) nitrate trihydrate (Cu(NO3)2·3H2O, Fujifilm Wako Pure Chemical Industries, Ltd., 99.9%), and zinc(II) nitrate hexahydrate (Zn(NO3)2·6H2O, Fujifilm Wako Pure Chemical Industries, Ltd., 99.9%) were dissolved in 120 mL of distilled water in a molar ratio of 20:80:10:10 Fe:Co:Cu:Zn to obtain a metal nitrate mixed solution. The water was evaporated by stirring the mixed solution on a hot plate at 80–90°C, and the dry catalyst powder was obtained. The resulting dry catalyst powder was calcined in a tubular calcination furnace at 500°C for 3 hours while circulating dry air at 50 mL / min, yielding a powder of catalyst particles containing a composite oxide containing Fe, Co, Cu, and Zn in a molar ratio of 20:80:10:10. 2-Propanol was added to the resulting catalyst particle powder and stirred to obtain a catalyst slurry containing catalyst particles. Catalyst #6, which had a 120 mg catalyst layer formed on the inner wall surface of a hollow tubular substrate, was obtained in the same manner as catalyst #1, except that this catalyst slurry was used. The catalyst layer contained a catalyst containing a composite oxide containing Fe, Co, Cu, and Zn in a molar ratio of 20:80:10:10.

[0050] Catalyst #7(Fe) A powder of Fe3O4 particles (Fujifilm Wako Pure Chemical Industries, Ltd., iron(III) oxide, iron(II)) was added to 2-propanol and stirred to obtain a catalyst slurry containing Fe3O4 particles. Catalyst body #7 was obtained in the same manner as catalyst body #1, except that this catalyst slurry was used. Catalyst body #7 had a 120 mg catalyst layer containing Fe3O4 formed on the inner wall surface of a hollow tubular substrate.

[0051] Catalyst #8(Co) 60 g of cobalt(II) nitrate hexahydrate (Co(NO3)2 6H2O) was added to an evaporating dish containing 80 mL of distilled water and stirred at room temperature to obtain a metal nitrate solution. The evaporating dish containing the metal nitrate solution was placed on a hot plate and stirred while maintaining a temperature of 80-90 °C to evaporate the water. The dried catalyst powder remaining on the evaporating dish was calcined in a tubular calcination furnace at 600 °C for 3 hours while circulating dry air at 50 mL / min to obtain a powder of catalyst particles containing cobalt oxide. The resulting catalyst particle powder was added to 2-propanol and stirred to obtain a catalyst slurry containing catalyst particles. Catalyst #8 was obtained in the same manner as catalyst #1, except that this catalyst slurry was used. It had a 120 mg catalyst layer containing cobalt oxide formed on the inner wall surface of a hollow tubular substrate.

[0052] Catalyst body #9 (Ni) Catalyst body #9 was prepared in the same manner as catalyst body #8, except that cobalt(II) nitrate hexahydrate was replaced with nickel nitrate hexahydrate. The catalyst body #9 had a 120 mg catalyst layer containing nickel oxide formed on the inner wall surface of a hollow tubular substrate.

[0053] 3.Solid carbon capture test -Test 1- Example 1 A solid carbon capture test was conducted using a reactor equipped with two hard glass tubular bodies (outer diameter 26 mm, length 750 mm, thickness 2 mm) serving as solid carbon capture reactors and a trap section installed between them. A cold trap was used as the trap section, which condenses water vapor by circulating cooling water at 4°C. A similar cold trap was also used in other solid carbon capture tests. The two solid carbon capture reactors, connected via piping and the trap section, were placed in a three-zone electric furnace (isolation zone length: 300 mm). Three catalysts #1 (Fe / Co) were inserted in series into each of the two carbon capture reactors. Prior to the solid carbon capture test, hydrogen (H2) was supplied to the gas flow path containing the solid carbon capture reactor at a flow rate of 0.12 L / min. The set temperature of the electric furnace was maintained at 600°C, and a hydrogen reduction pretreatment was performed for 2 hours. The gas supply was then switched to nitrogen (N2) (flow rate: 0.2 L / min), and the set temperature of the electric furnace was changed to 430 °C. When the temperature inside the reactor stabilized at 430 °C, the gas supply was switched to a feed gas (total flow rate: 0.4 L / min) containing CO (flow rate: 0.15 L / min), H2 (flow rate: 0.2 L / min), and N2 (flow rate: 0.05 L / min), and the solid carbon capture test was initiated. The feed gas was supplied to the reactor at a pressure of 0.1 MPa from gas cylinders containing each gas component via mass flow controllers. The pressure at the outlet of the solid carbon capture reactor was open to atmospheric pressure. After the solid carbon capture test was performed for 5 hours, the gas supply was switched to nitrogen (N2) (flow rate: 0.2 L / min), and the solid carbon capture test was terminated. The temperature of the solid carbon capture reactor was then lowered to room temperature. Then, catalyst body #1 was removed from the solid carbon capture reactor. Solid carbon deposited from the feed gas was attached to the catalyst layer of catalyst body #1. The masses of six catalyst bodies #1 containing the deposited solid carbon were measured, and the amount of collected solid carbon (mass of deposited solid carbon) was calculated. The carbon collection rate was calculated using the following formula, which is the ratio of the carbon content of CO in the supplied feed gas that was converted into collected carbon. In the formula, F (CO) is the amount of CO in the source gas per unit time. The collection time was 5 hours.

number

[0054] Comparative Example 1 A single-stage reactor having one hard glass tubular body and no trap section was used as a solid carbon capture reactor. Six catalyst bodies #1 (300 mm long) were inserted in series into one hard glass tubular body. A solid carbon capture test was conducted under the same conditions as in Example 1.

[0055] result FIG. 6 is a graph showing the carbon collection efficiencies in Example 1 and Comparative Example 1. In Example 1, the total carbon collection efficiencies for the six catalyst bodies was 41.3 mass%. On the other hand, in Comparative Example 1, the total carbon collection efficiencies for the six catalyst bodies was 31.6 mass%. As in Example 1, by dividing the six catalyst bodies into two reactor stages of three each and installing a trap section for trapping moisture between them, the carbon collection efficiencies were significantly improved compared to Comparative Example 1, in which six catalyst bodies #1 were connected in series. This result confirmed the great effect of the trap section for trapping moisture.

[0056] -Test 2- Example 2A A solid carbon capture test was conducted using a reactor having the same configuration as the reactor 101 in Figure 1, except for the dry reforming section. Three hard glass tubular bodies (outer diameter 26 mm, length 750 mm, thickness 2 mm) were used as reactors for the first-stage solid carbon capture section 11, the second-stage solid carbon capture section 12, and the third-stage solid carbon capture section 13. Five catalyst bodies #1 (Fe / Co) were inserted in series into each of the three hard glass tubular bodies. The first to third-stage reactors were placed in an electric furnace. Prior to the solid carbon capture test, hydrogen (H) was supplied at a flow rate of 0.2 L / min to the gas flow path containing the first, second, and third reactors. The set temperature of the electric furnace used to heat the first, second, and third reactors was maintained at 600 °C, and hydrogen reduction was performed for 2 h. The gas supply was then switched to nitrogen (N) (flow rate: 200 mL / min), and the set temperature of the electric furnace was changed to 450 °C. Once the reactor temperature stabilized at 450 °C, the gas supply was switched to a feed gas (total flow rate: 0.5 L / min) containing CO (flow rate: 150 mL / min), H (flow rate: 220 mL / min), CO (flow rate: 30 mL / min), and N (flow rate: 100 mL / min), and the solid carbon capture test began. The feed gas was supplied to the reactor at a pressure of 0.1 MPa from gas cylinders containing the respective gas components via mass flow controllers. The pressure at the outlet of the solid carbon capture reactor was open to atmospheric pressure. After the solid carbon capture test was performed for 5 hours, the gas supplied was switched to nitrogen (N) (flow rate: 0.2 L / min) to terminate the solid carbon capture test, and the temperature of the reactor was lowered to room temperature. As in Example 1, the carbon capture efficiency was calculated from the amount of solid carbon captured.

[0057] Examples 2B to 2F and Comparative Examples 2A to 2C A solid carbon capture test was carried out in the same manner as in Example 2A, except that the catalyst #1 (Fe / Co) was replaced with the catalyst shown in Table 1. After the test, the carbon capture rate was calculated from the amount of solid carbon captured.

[0058] result Table 1 and FIG. 7 show the carbon collection efficiencies of each solid carbon collection section in Examples 2B to 2F and Comparative Examples 2A to 2C. In the table, the carbon collection efficiencies of the second-stage solid carbon collection section are the total carbon collection efficiencies of the first- and second-stage solid carbon collection sections, and the carbon collection efficiencies of the third-stage solid carbon collection section are the total carbon collection efficiencies of the first-, second-, and third-stage solid carbon collection sections. This is also true for other test results. In Examples 2A to 2F, it was confirmed that solid carbon could be captured at a higher carbon collection efficiencies by combining a catalyst containing a metal oxide containing Fe and a specific non-ferrous metal with a trap section. In Comparative Examples 2A to 2C, which used a catalyst containing a metal oxide containing only Fe, Co, or Ni, there was little tendency for the introduction of a trap section to improve the carbon collection efficiencies.

[0059] [Table 1]

[0060] -Test 3- Example 3A Copper nitrate trihydrate (Cu(NO3)2·3H2O) and zinc nitrate hexahydrate (Zn(NO3)2·6H2O) were dissolved in distilled water at a Cu:Zn molar ratio of 1:1 to prepare a metal nitrate mixed aqueous solution. This metal nitrate mixed aqueous solution was added to the Catalysis Society reference catalyst JRC-ALO-7 (alumina particles, average particle size 3.2 mm, specific surface area 180 m). 2 Zn / g) was added. While stirring the mixture, the mixture was heated at 80-90°C using a hot plate to evaporate the water, yielding a granular catalyst containing alumina particles and a mixed oxide containing Cu and Zn supported on the alumina particles. This granular catalyst was calcined at 300°C for 2 hours using a tubular calciner while circulating dry air at 0.05 L / min, yielding a granular catalyst (Cu / Zn / Al2O3) for the reverse water gas shift reaction. This granular catalyst contained a metal oxide containing Cu and Zn. The ratio of the amount of the metal oxide containing Cu and Zn (supported amount) to the mass of the alumina particles was 18 mass%.

[0061] A solid carbon capture test was conducted using a reactor with the same configuration as the reactor 102 in Figure 4, except for the dry reforming section. Five catalyst bodies #3 (Fe / Co / K) were inserted in series into each of the reactors of the first-stage solid carbon capture section 11 and the second-stage solid carbon capture section 12. A granular catalyst (Cu / Zn / Al2O3) for the reverse water gas shift reaction was inserted into the reactor of the reverse water gas shift reaction section 30 to form a catalyst layer with a length of 250 mm. Prior to the solid carbon capture test, the catalyst bodies #3 (Fe / Co / K) in the first-stage solid carbon capture section 11 and the second-stage solid carbon capture section 12 were pretreated by hydrogen reduction at 600°C for 2 hours. Prior to the solid carbon capture test, the granular catalyst in the reverse water gas shift reaction section 30 was subjected to oxidation treatment with dry air at 350°C for 2 hours. The solid carbon capture test was then conducted under the same conditions as in Example 2A. However, the temperature of the electric furnace for heating the first-stage solid carbon capture section 11 and the second-stage solid carbon capture section 12 was 450° C., and the temperature of the electric furnace for heating the reverse water gas shift reactor 30 was 520° C. The carbon capture efficiency was determined after the solid carbon capture test was carried out for 5 hours.

[0062] Example 3B A solid carbon capture test was carried out under the same conditions as in Example 3A, except that no particulate catalyst for the reverse water gas shift reaction was inserted into the reactor of the reverse water gas shift reaction section 30 in Example 3A.

[0063] [Table 2]

[0064] result Table 2 shows the carbon capture efficiency in the solid carbon capture section of Example 3A or 3B. Comparison of Example 3A and Example 3B confirmed that the introduction of a reverse water-gas shift reaction catalyst further increased the carbon capture efficiency.

[0065] -Test 4- Example 4A A solid carbon capture test was carried out under the same conditions as in Example 2A, except that the pressure of the raw material gas was changed to 0.94 MPa.

[0066] result Table 3 shows the carbon capture efficiency in each of the first to third solid carbon capture sections. Comparison with Example 2C confirmed that the carbon capture efficiency was further increased by pressurizing the gas flow path of the reactor.

[0067] [Table 3]

[0068] -Test 5- Example 5A A solid carbon capture test was carried out under the same conditions as in Example 2C and Example 4A, except that the pressure of the raw material supply gas and the pressure in the gas flow path in the reactor were set to 0.94 MPa, and the heating temperature of the catalyst body while the raw material supply gas was flowing was set to 380°C, 410°C, 430°C, 450°C, 470°C, 500°C, 550°C, 600°C, or 650°C.

[0069] Example 5B A solid carbon capture test was carried out under the same conditions as in Example 5A, except that the pressure of the raw material supply gas and the pressure in the gas flow path in the reactor were atmospheric pressure (0.10 MPa).

[0070] result 8 is a graph showing the relationship between the carbon capture efficiency and temperature in Example 5A or Example 5B. The carbon capture efficiency here is a ratio calculated from the total amount of solid carbon captured in the first, second, and third solid carbon capture sections. It was confirmed that pressurizing the gas flow path of the reactor further increases the carbon capture efficiency over a wide temperature range. [Explanation of symbols]

[0071] 1...substrate, 3...catalyst layer, 5...solid carbon capture catalyst body, 6...solid carbon capture reactor, 8...heater, 11, 12, 13...solid carbon capture section, 20a, 20b, 20c, 20d...trap section, 30...reverse water gas shift reaction section, 31...reverse water gas shift reaction reactor, 32...reverse water gas shift reaction catalyst body, 40...dry reforming section, 41...dry reforming reactor, 42...dry reforming catalyst body, 50...methanation section, 51...methanation reactor, 52...methanation catalyst body, 101, 102, 103...reactor, G0...feedstock gas

Claims

1. preparing a reaction apparatus having a solid carbon capture reactor and a solid carbon capture catalyst body, wherein the solid carbon capture catalyst body is provided in the solid carbon capture reactor, or the solid carbon capture catalyst body also serves as the solid carbon capture reactor, the reaction apparatus comprising a plurality of solid carbon capture units and a trap unit for trapping moisture, and a gas flow path including the solid carbon capture reactor and the trap unit; supplying a raw material gas containing carbon monoxide and hydrogen to the gas flow passage while heating the solid carbon capture catalyst body, thereby depositing solid carbon on the solid carbon capture catalyst body; 1. A method for capturing solid carbon, comprising: A plurality of the solid carbon traps are connected in series along the gas flow path, and the trap unit is disposed between two adjacent solid carbon traps on the gas flow path; The method, wherein the solid carbon capture catalyst body has a catalyst layer containing a metal oxide containing Fe and a non-ferrous metal, and the non-ferrous metal is one or more selected from the group consisting of Co, Mg, Ni, Mn, Mo, K, Na, Li, Ca, Cs, Sr, Ba, La, Ce, Pd, Nd, Cu, and Zn.

2. The method of claim 1 , wherein the pressure in the gas flow path to which the source gas is supplied exceeds atmospheric pressure.

3. the reaction apparatus further comprises a reverse water gas shift reaction section having a reverse water gas shift reaction reactor and a reverse water gas shift reaction catalyst provided in the reverse water gas shift reaction reactor; the gas flow path further comprises a reactor for the reverse water gas shift reaction; the reverse water gas shift reactor is disposed between two adjacent solid carbon capture units in the gas flow path; 2. The method of claim 1, wherein the reactor comprises the trapping section disposed between the reverse water gas shift reactor and the solid carbon trapping section upstream in the gas flow path, and the trapping section disposed between the reverse water gas shift reactor and the solid carbon trapping section downstream in the gas flow path.

4. The method according to claim 3 , wherein the reverse water gas shift reaction catalyst body has a catalyst layer containing a metal oxide containing Cu and Zn.

5. the reaction device further comprises a dry reforming section having a dry reforming reactor and a dry reforming catalyst body provided in the dry reforming reactor, the dry reforming section being connected to the solid carbon capture section located most upstream in the gas flow path, 2. The method according to claim 1, wherein a gas containing methane and carbon dioxide is supplied to the dry reforming unit, and a gas containing carbon monoxide and hydrogen discharged from the dry reforming unit is supplied as the raw material gas to the gas flow path including the solid carbon capture unit.

6. the reaction apparatus further comprises a methanation unit having a methanation reactor and a methanation catalyst body provided in the methanation reactor and connected to the dry reforming unit; The method according to claim 5 , wherein a gas containing carbon dioxide and hydrogen is supplied to the methanation unit, and a gas containing methane and carbon dioxide discharged from the methanation unit is supplied to the dry reforming unit.

7. The method according to claim 1 , wherein the raw material gas is supplied to the gas flow passage while the solid carbon trapping catalyst body is heated to 500° C. or less.

8. 8. The method according to claim 1, wherein the proportion of the non-ferrous metal in the catalyst layer is 40 mol % or more based on the total amount of the Fe and the non-ferrous metal.

9. a plurality of solid carbon capture units each having a solid carbon capture reactor and a solid carbon capture catalyst body, the solid carbon capture catalyst body being provided in the solid carbon capture reactor, or the solid carbon capture catalyst body also serving as the solid carbon capture reactor; a trap portion that traps moisture; Equipped with a gas flow path including the solid carbon capture reactor and the trap section is formed; A plurality of the solid carbon trapping units are arranged in series along the gas flow path, and the trap unit is arranged between two adjacent solid carbon trapping units on the gas flow path, a reaction apparatus, wherein the solid carbon capture catalyst body has a catalyst layer containing a metal oxide containing Fe and a non-ferrous metal, and the non-ferrous metal is one or more selected from the group consisting of Co, Mg, Ni, Mn, Mo, K, Na, Li, Ca, Cs, Sr, Ba, La, Ce, Pd, Nd, Cu, and Zn.

10. the reaction apparatus further comprises a reverse water gas shift reaction section having a reverse water gas shift reaction reactor and a reverse water gas shift reaction catalyst provided in the reverse water gas shift reaction reactor; the gas flow path further comprises a reactor for the reverse water gas shift reaction; the reverse water gas shift reactor is disposed between two adjacent solid carbon capture units in the gas flow path; 10. The reactor according to claim 9, further comprising: the trapping section disposed between the reverse water gas shift reactor and the solid carbon trapping section located upstream in the gas flow path; and the trapping section disposed between the reverse water gas shift reactor and the solid carbon trapping section located downstream in the gas flow path.

11. 11. The reactor of claim 10, wherein the reverse water gas shift reaction catalyst comprises a metal oxide containing Cu and Zn.

12. 10. The reaction apparatus according to claim 9, further comprising a dry reforming section having a dry reforming reactor and a dry reforming catalyst body provided in the dry reforming reactor, the dry reforming section being connected to the solid carbon capture section located most upstream in the gas flow path.

13. 13. The reaction apparatus according to claim 12, further comprising a methanation section having a methanation reactor and a methanation catalyst body provided in the methanation reactor, the methanation section being connected to the dry reforming section.

14. 14. The reaction apparatus according to claim 9, wherein the proportion of the non-ferrous metal in the catalyst layer is 40 mol % or more with respect to the total amount of the Fe and the non-ferrous metal.

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