Carbon and / or hydrogen production apparatus, and carbon and / or hydrogen production method

Abstract

A carbon and / or hydrogen production apparatus comprising at least a porous catalyst in which metal particles are supported, an oxidant supply means which supplies an oxidant to the porous catalyst, and a carbon-containing gas supply means which supplies, to the porous catalyst, a carbon-containing gas which contains carbon in the constituent elements, wherein the porous catalyst is formed into a plate-like shape, the carbon-containing gas is supplied to one surface side of the porous catalyst, and the oxidant is supplied to the other surface side of the porous catalyst.

Description

Carbon and / or hydrogen production device, carbon and / or hydrogen production method

[0001] The present invention relates to a carbon and / or hydrogen production device for producing carbon and / or hydrogen from a carbon-containing gas, and a carbon and / or hydrogen production method using the same. This application claims priority based on Japanese Patent Application No. 2024-090144, filed in Japan on June 3, 2024, the contents of which are incorporated herein by reference.

[0002] Recently, carbon dioxide (CO ２ The use of hydrogen energy, which does not emit gases, is being expanded. For example, hydrogen vehicles and hydrogen gas power generation use almost exclusively water vapor (H ２ CO2, which is considered to be the cause of climate change, is emitted only in the form of CO2. ２ It is said to contribute to achieving zero emissions, which means virtually zero emissions.

[0003] However, currently, most industrial hydrogen production is carried out by steam reforming of hydrocarbon gases, such as methane (CH ４ +2H ２ O → 4H ２ +CO ２ ) and CO ２ This is also currently occurring.

[0004] For this reason, CH ４ From CO ２ As a method for generating hydrogen (turquoise hydrogen) without generating carbon dioxide, the cracking reaction of hydrocarbon gas (carbon deposition reaction: C ｘ H ｙ A method for producing carbon and hydrogen by utilizing the reaction (xC + yH) has been studied (for example, Non-Patent Document 1).

[0005] Simultaneous and Continuous Production of Carbon Nanotubes and Hydrogen by Catalytic CH4 Decomposition in a Pressurized Fluidized-Bed Reactor, Industrial & Engineering Chemistry Research, 2024, 63, 930-941.

[0006] However, when hydrogen is produced from hydrocarbon gas by the method disclosed in Non-Patent Document 1, the produced carbon accumulates on the surface of the catalyst and covers the catalyst, which causes a decrease in the area of ​​the exposed part of the catalyst as the reaction progresses, resulting in a problem of reduced reactivity.

[0007] The present invention has been proposed in view of the above-mentioned problems, and aims to provide a carbon and / or hydrogen production device and a carbon and / or hydrogen production method that can prevent carbon from being deposited on a porous catalyst and reducing reactivity when carbon-containing gas is brought into contact with the porous catalyst to produce carbon.

[0008] In order to solve the above problems, a carbon and / or hydrogen production apparatus and a carbon and / or hydrogen production method according to one embodiment of the present invention propose the following means: (1) A carbon and / or hydrogen production apparatus according to Aspect 1 of the present invention includes at least a porous catalyst carrying metal particles, an oxidant supply means for supplying an oxidant to the porous catalyst, and a carbon-containing gas supply means for supplying a carbon-containing gas containing carbon as a constituent element to the porous catalyst, the porous catalyst being formed into a plate shape, the carbon-containing gas being supplied to one side of the porous catalyst, and the oxidant being supplied to the other side of the porous catalyst.

[0009] (2) Aspect 2 of the present invention is the carbon and / or hydrogen production device according to Aspect 1, wherein the porous catalyst is formed by supporting the metal particles on a porous body containing an ion-conductive solid oxide.

[0010] (3) Aspect 3 of the present invention is the carbon and / or hydrogen production device according to aspect 1 or 2, wherein the metal particles contain Fe and / or Co.

[0011] (4) Aspect 4 of the present invention is the carbon and / or hydrogen production device according to any one of Aspects 1 to 3, wherein the oxidant is H ２ O gas and / or O ２ Includes gas.

[0012] (5) Aspect 5 of the present invention is the carbon and / or hydrogen production apparatus according to any one of Aspects 1 to 4, wherein the carbon-containing gas is a hydrocarbon gas, CO ２ , CO.

[0013] (6) A sixth aspect of the present invention is the carbon and / or hydrogen production device according to any one of the first to fifth aspects, further comprising a solid oxide cell having an anode made of the porous catalyst, a cathode made of a material containing a metal oxide, and a solid electrolyte layer disposed between the anode and the cathode.

[0014] (7) A seventh aspect of the present invention is the carbon and / or hydrogen production device according to the sixth aspect, wherein the anode includes a porous region in which the porous catalyst is formed, and a conductive region made of a conductor formed into a mesh shape.

[0015] (8) Aspect 8 of the present invention is the carbon and / or hydrogen production device according to aspect 6 or 7, wherein a hydrocarbon gas and an oxidant are supplied to the solid oxide cell, and electricity is generated between the anode and the cathode.

[0016] (9) Aspect 9 of the present invention is the carbon and / or hydrogen production device according to aspect 6 or 7, wherein the solid oxide cell is provided with CO ２ Alternatively, CO is supplied, and power is applied between the anode and the cathode to generate CO ２ Or, electrolysis of CO is carried out.

[0017] (10) A carbon and / or hydrogen production device according to a tenth aspect of the present invention includes a porous catalyst that produces carbon from a carbon-containing gas that contains carbon as a constituent element, and an oxidant layer forming means that forms an oxidant layer on a surface of the porous catalyst, wherein the oxidant layer forming means forms the oxidant layer between the produced carbon and the surface of the porous catalyst when carbon is produced by the porous catalyst.

[0018] (11) A carbon and / or hydrogen production method according to Aspect 11 of the present invention is a carbon and / or hydrogen production method using the carbon and hydrogen production apparatus according to any one of Aspects 1 to 9, comprising the steps of supplying hydrocarbons to the porous catalyst and decomposing them into carbon and hydrogen, thereby depositing the carbon on a surface of the porous catalyst, and supplying an oxidant to form an oxidant layer between the surface of the porous catalyst and the deposited carbon, thereby causing the deposited carbon to peel off from the surface of the porous catalyst.

[0019] (12) A carbon and / or hydrogen production method according to Aspect 12 of the present invention is a method for producing carbon and hydrogen using the carbon and hydrogen production apparatus according to any one of Aspects 6 to 9, comprising: a step of supplying a hydrocarbon to the solid oxide cell and decomposing the hydrocarbon into carbon and hydrogen, thereby depositing the carbon on a surface of the anode; and a step of supplying an oxidant to form an oxidant layer between the surface of the anode and the deposited carbon, thereby causing the deposited carbon to peel off from the surface of the anode, wherein the density of the current flowing between the anode and the cathode is 100 mA / cm. ２ That's all.

[0020] According to the present invention, it is possible to provide a carbon and / or hydrogen production device and a carbon and / or hydrogen production method that can prevent carbon from being deposited on the porous catalyst and reducing reactivity when carbon-containing gas is brought into contact with the porous catalyst to produce carbon.

[0021] FIG. 1 is a schematic diagram of a main part showing a carbon and hydrogen production device according to a first embodiment of the present invention. FIG. 2 is a schematic diagram of a main part showing a carbon and hydrogen production device according to a second embodiment of the present invention. FIG. 3 is an enlarged plan view of a main part showing the shape of an anode in the second and third embodiments of the present invention. FIG. 4 is a schematic diagram of a main part showing a carbon production device according to a third embodiment of the present invention. FIG. 5 is an EDS photograph of a Ni / YSZ porous body carrying Fe particles. FIG. 6 is a photograph showing the results of a verification example of the second embodiment. FIG. 7 is a schematic diagram showing the configuration of a carbon production device according to a verification example of the third embodiment. FIG. 8 is an SEM photograph showing the results of a verification example of the third embodiment.

[0022] Hereinafter, a carbon and / or hydrogen production apparatus according to one embodiment of the present invention and a carbon and / or hydrogen production method using the same will be described with reference to the drawings. Note that the embodiment shown below is specifically described to provide a better understanding of the gist of the invention, and does not limit the present invention unless otherwise specified. Furthermore, the drawings used in the following description may show essential parts enlarged for convenience in order to make the features of the present invention easier to understand, and the dimensional ratios of each component may not necessarily be the same as those in reality.

[0023] 1 is a schematic diagram of a main part of a carbon and hydrogen production device according to a first embodiment of the present invention. The carbon and hydrogen production device 10 of this embodiment includes a porous catalyst 11 formed in a plate shape, a support 12 supporting the porous catalyst 11, and a H-type catalyst layer on the other surface 11b of the porous catalyst 11. ２ H supplying O gas ２ O supply means (oxidant supply means) 13 and a carbon-containing gas, propane (C ３ H ８ ) C ３ H ８ The apparatus includes a gas supply means (carbon-containing gas supply means) 14 and a heating means 15 for heating the porous catalyst 11. The porous catalyst 11 and the support 12 supporting the porous catalyst 11 may be housed in a heat-resistant chamber (not shown) or the like.

[0024] The porous catalyst 11 is composed of a porous body containing an ion-conductive solid oxide supporting metal particles. ２ O ３ Stabilized ZrO ２ (YSZ) and Sc ２ O ３ Stabilized ZrO ２ (ScSZ), etc. Such a porous catalyst 11 is fixed to, for example, one open end of a cylindrical support 12 so as to close it.

[0025] Examples of the metal particles include iron (Fe) particles, cobalt (Co) particles, etc. The porous body constituting the porous catalyst 11 of this embodiment may be the above-mentioned Ni / YSZ porous body or Ni / ScSZ porous body, with the above-mentioned Fe particles or Co particles supported on at least the surface thereof.

[0026] H ２ The O supply means 13 supplies gaseous water, for example, H ２ It may consist of a water tank for supplying O gas, a heater, a pump, etc. ３ H ８ The gas supply means (carbon-containing gas supply means) 14 may be composed of an LP gas cylinder containing liquefied propane or the like.

[0027] H of this embodiment ２ The O supply means 13 may be an oxidizing agent supply means. The oxidizing agent may be the above-mentioned H ２ In addition to O gas, for example, O ２ Gas, CO ２ In particular, the oxidizing agent may be H ２ O gas or O ２ Gases allow carbon and hydrogen to be produced at low cost.

[0028] The carbon-containing gas in this embodiment may be any hydrocarbon gas. ３ H ８ In addition to gases, for example, methane (CH ４ ) gas, ethane (C ２ H ６ ) gas, butane (C ４ H １０ In particular, if a hydrocarbon gas with a large carbon number is used, carbon and hydrogen can be produced more efficiently.

[0029] The heating means 15 may be any of various heaters, such as an infrared heater, a high-frequency heater, an induction heater, etc. The heating means 15 of this embodiment may be any heater capable of raising the temperature of the porous catalyst 11 to, for example, about 700°C to 1000°C.

[0030] When producing carbon and hydrogen by the carbon and hydrogen production method using the carbon and hydrogen production apparatus 10 of the first embodiment as described above, first, the porous catalyst 11 is heated to, for example, about 800°C by the heating means 15 (heating step).

[0031] Next, H ２ O supply means 13 to H ２ O gas is supplied. ２ The supply flow rate of O gas may be, for example, 10 mL / min to 100 mL / min.

[0032] In addition, H supplied to the other surface 11b of the porous catalyst 11 ２ O gas permeates through the numerous pores of the porous catalyst 11 to the one surface 11a side. ２ In order to efficiently allow O gas to permeate the porous catalyst 11, H ２ It is also preferable to increase the supply pressure of O gas to, for example, 2000 hPa or more.

[0033] In addition, on the one surface 11a side of the heated porous catalyst 11, C ３ H ８ Gas supply means to C ３ H ８ Gas is supplied. At this time, C ３ H ８ It is also preferable to supply Ar gas, which is an inert gas, together with the gas. ３ H ８ The gas supply flow rate may be, for example, 10 mL / min to 100 mL / min.

[0034] By the above-described process, the C in contact with the one surface 11a of the porous catalyst 11 heated to, for example, 800°C is ３ H ８ The gas is converted into carbon C and hydrogen gas H by the catalytic action of the porous catalyst 11 as shown in the following formula (1): ２ The carbon C thus produced is deposited on the surface 11a of the porous catalyst 11 (carbon production step). The carbon C thus produced is, for example, amorphous carbon. ３ H ８ →3C+4H ２ ...(1)

[0035] In addition, part of the carbon C generated on the one surface 11a of the porous catalyst 11 is mixed with H ２ It reacts with O gas to produce CO gas and hydrogen gas H as shown in the following formula (2): ２ C + H ２ O → CO + H ２ ...(2)

[0036] Then, H2O, which is supplied from the other surface 11b of the porous catalyst 11 and passes through the porous catalyst 11 to reach the one surface 11a, ２ The O gas is liquefied by the temperature drop when it comes into contact with the deposited carbon C, and water vapor (H ２ O) layer Q is formed. In this way, by forming the water vapor layer Q on the one surface 11 a side of the porous catalyst 11, the accumulated carbon C is peeled off from the one surface 11 a side of the porous catalyst 11 by its own weight every time a certain amount of carbon C is accumulated (carbon peeling process).

[0037] Furthermore, the water constituting the water vapor layer Q is converted back into H by heating the porous catalyst 11. ２ A part of the O gas reacts with a part of the produced carbon C to form CO gas and hydrogen gas H as shown in the above formula (2). ２ This results in:

[0038] In addition, H ２ When an oxidizing agent supply means is used in the O supply means 13 portion, H ２ In the same process as with O gas, an oxidant layer is formed between the one surface 11 a of the porous catalyst 11 and the carbon C deposited on the one surface 11 a of the porous catalyst 11. As the oxidant layer is formed on the one surface 11 a of the porous catalyst 11, the deposited carbon C peels off from the one surface 11 a of the porous catalyst 11 due to its own weight every time a certain amount of carbon C is deposited (carbon peeling process).

[0039] As described above, according to the carbon and hydrogen production device 10 of this embodiment, the hydrocarbon gas C ３ H ８ From the gas, CO ２ Carbon C and hydrogen gas H without generating gas ２and can be generated.

[0040] Then, the C by such a porous catalyst 11 ３ H ８ During the decomposition of the gas, H ２ By supplying O gas, a water vapor layer Q is formed between the porous catalyst 11 and the generated carbon C, causing the carbon C to intermittently peel off. As a result, the entire surface 11a of the porous catalyst 11 is covered with a large amount of carbon C, and the decomposition reaction shown in formula (1) does not stop in a short time. ２ By supplying O gas from the other side, the adhesive force between the carbon and the porous catalyst is reduced, and the carbon can be easily peeled off by external vibration.

[0041] As a result, C using the porous catalyst 11 ３ H ８ The gas decomposition reaction can be carried out continuously for a long period of time, and carbon C and hydrogen gas H ２ It is possible to generate these signals efficiently and at low cost with a simple configuration.

[0042] 2 is a schematic diagram of a carbon and hydrogen production device according to a second embodiment of the present invention. The carbon and hydrogen production device 20 of this embodiment includes an SOFC (Solid Oxide Fuel Cell) 29, which is an example of a solid oxide cell, an anode 21 supporting the SOFC 29, and an oxygen gas O 2 supplied to the other surface 29b of the SOFC 29. ２ Supply O ２ The gas supply means 23 and the one surface 29 a of the SOFC 29 are connected to each other. ３ H ８ ) C ３ H ８ Gas supply means (carbon-containing gas supply means) 24, and H ２ H supplying O gas ２ The system includes an O supply means 26 and a heating means 25 for heating the SOFC 29. The SOFC 29 and the anode 21 supporting the SOFC 29 may be housed in a heat-resistant chamber (not shown) or the like.

[0043] The SOFC 29 has an anode (porous catalyst: fuel electrode) 21 made of a porous catalyst, a cathode (air electrode) 27 made of a material containing a metal oxide, and a solid electrolyte layer 28 disposed between the anode 21 and the cathode 27. Of these, the exposed surface of the cathode 27 constitutes the other surface 29b of the SOFC 29, and the exposed surface of the anode 21 constitutes the one surface 29a of the SOFC 29.

[0044] As shown in FIG. 3, the anode 21 of this embodiment is composed of a porous region 21a formed in a disk shape and a ring-shaped conductive region 21b formed to surround the periphery of this porous region 21a.

[0045] The porous body region 21 a is made of a porous body containing an ion-conductive solid oxide supporting metal particles. The porous body constituting the porous body region 21 a of this embodiment may be any porous body having Fe particles supported on at least the surface of the porous body.

[0046] The conductive region 21b is made of a mesh material m1 made of silver, with silver paste m2 embedded in the gaps between the mesh material m1 and the conductive region 21b. Note that the conductive region 21b can also be made of a conductive material other than silver, such as copper or aluminum.

[0047] The cathode (air electrode) 27 is made of lanthanum strontium manganite (LaSrMnO ３ A porous body made of a composite material of Ni / YSZ and LSM (Lysine Sulfide Molybdenum Monomer) can be used. When combined with Ni / YSZ, LSM can form a stable interface and can also absorb oxygen ions (O ２－ ) can be transmitted.

[0048] The solid electrolyte layer 28 is made of Y ２ O ３ Stabilized ZrO ２ YSZ is used. The presence of oxygen vacancies in YSZ allows oxygen ions (O ２－ The vacancy diffusion mechanism of YSZ is enhanced at temperatures above 700°C.

[0049] O ２ The gas supply means 23 is O ２It may be composed of an oxygen tank for supplying gas, a pump, etc. ３ H ８ The gas supply means (carbon-containing gas supply means) 24 may be composed of an LP gas cylinder containing liquefied propane. ２ The O supply means 26 supplies gaseous water, for example, H 2 O 2 at 100° C. or higher. ２ The O gas supply system may be configured with a water tank, a heater, a pump, etc. ２ Although the gas supply means 23 is provided, an oxidizing agent supply means similar to that in the first embodiment may also be provided.

[0050] The carbon-containing gas in this embodiment may be any hydrocarbon gas. ３ H ８ In addition to gases, for example, methane (CH ４ ) gas, ethane (C ２ H ６ ) gas, butane (C ４ H １０ In particular, if a hydrocarbon gas with a large carbon number is used, carbon can be produced more efficiently.

[0051] The heating means 25 may be any of various heaters, such as an infrared heater, a high-frequency heater, an induction heater, etc. The heating means 25 of this embodiment may be any heater capable of raising the temperature of the anode 21 and the cathode 27 constituting the SOFC 29 to, for example, about 700°C to 1000°C.

[0052] When producing carbon and hydrogen by the carbon and hydrogen production method using the carbon and hydrogen production device 20 of the second embodiment as described above, first, the anode 21 and the cathode 27 constituting the SOFC 29 are each heated to, for example, about 800°C by the heating means 25 (heating step).

[0053] Next, the cathode (air electrode) 27 constituting the other surface 29 b of the heated SOFC 29 was ２ From the gas supply means 23 ２ Supply gas. ２The gas supply flow rate may be, for example, 10 mL / min to 100 mL / min.

[0054] At the same time, the anode (fuel electrode) 21 constituting the one surface 29a side of the heated SOFC 29 is charged with C ３ H ８ Gas supply means 24 to C ３ H ８ Gas is supplied. ２ O supply means 26 to H ２ O gas is supplied. ３ H ８ Gas and H ２ The supply flow rate of O gas may be, for example, 10 mL / min to 100 mL / min.

[0055] By the above-mentioned process, the O in contact with the one surface 29a of the SOFC 29 heated to, for example, 800° C. ２ The gas passes through the porous body made of the LSM-Ni / YSZ composite material that constitutes the cathode (air electrode) 27, and converts into oxygen ions (O ２－ ), propagates through the solid electrolyte layer 28 , and reaches the anode (porous catalyst: fuel electrode) 21 .

[0056] Then, at the anode 21, due to the catalytic action of the porous body, carbon C and hydrogen gas H are reacted as shown in the following formula (1): ２ The carbon C thus produced is deposited in the porous region 21a of the anode 21 (carbon production step). The carbon C thus produced is, for example, amorphous carbon. ３ H ８ →3C+4H ２ ...(1)

[0057] In addition, the hydrogen gas H generated by the formula (1) ２ is the oxygen ion (O ２－ ) to form H ２ O gas is produced. ２ +O ２－ →H ２ O + 2e － ...(3) Also, part of the carbon C produced on the anode 21 is converted into H produced by the formula (3). ２It reacts with O gas to produce CO gas and hydrogen gas H as shown in the following formula (2): ２ C + H ２ O → CO + H ２ ...(2)

[0058] During the reaction of formula (2) as described above, electricity is generated between the conductive region 21b of the anode 21 and the cathode 27, thereby generating electricity. This power generation process is the power generation mechanism of a so-called fuel cell.

[0059] In this embodiment, too, H supplied to the one surface 29a of the SOFC 29, i.e., the anode (porous catalyst) 21 ２ The O gas acts as a water vapor (H ２ O) layer Q. In this way, by forming the water vapor layer Q in the porous body region 21 a of the anode 21, the deposited carbon C peels off from the porous body region 21 a due to its own weight every time a certain amount of carbon C is deposited (carbon peeling process).

[0060] In addition, a part of the water vapor layer Q reacts with a part of the generated carbon C to produce CO gas and hydrogen gas H as shown in the above formula (2). ２ This results in:

[0061] As described above, according to the carbon and hydrogen production device 20 of this embodiment, the hydrocarbon gas C ３ H ８ From the gas, CO is ２ Carbon C and hydrogen gas H without generating gas ２ and can be generated.

[0062] Then, the anode (porous catalyst) 21 ３ H ８ During the decomposition of the gas, H ２ By supplying O gas, a water vapor layer Q is formed between the porous body region 21a of the anode 21 and the carbon C deposited thereon, causing the carbon C to intermittently peel off. As a result, the entire porous body region 21a of the anode 21 is covered with a large amount of deposited carbon C, and the decomposition reaction shown in formula (1) does not stop in a short time.

[0063] This allows for the C ３ H ８ It is now possible to carry out the gas decomposition reaction continuously for a long period of time, enabling continuous power generation and the decomposition of carbon (C) and hydrogen gas (H). ２ This makes it possible to realize the continuous generation of the above-mentioned components efficiently and at low cost with a simple configuration.

[0064] 4 is a schematic diagram of a main part of a carbon production apparatus according to a third embodiment of the present invention. The same components as those in the second embodiment are denoted by the same reference numerals, and redundant explanations will be omitted. In the carbon production apparatus 30 of this embodiment, a carbon-containing gas, CO 2 , is supplied to one surface 39 a of an SOEC (Solid Oxide Electrolsys Cell) 39, which is an example of a solid oxide cell. ２ CO that supplies ２ Gas supply means (carbon-containing gas supply means) 34, hydrogen gas H ２ H that supplies ２ Gas supply means 46, and H ２ H supplying O gas ２ and an O supply means 36.

[0065] In this embodiment, H ２ The O supply means 36 is configured from a bubbling device containing liquid water, and CO ２ Gas and H ２ By bubbling gas through it, H ２ It may be configured to generate O gas (water vapor).

[0066] In addition, oxygen gas O ２ Supply O ２ Gas supply means 33 is provided. ２ In addition, it is also preferable to supply Ar gas, which is an inert gas. ２ Although the gas supply means 33 is provided, an oxidizing agent supply means similar to that in the second embodiment may also be provided.

[0067] In this embodiment, power is applied between the anode 38 and the conductive region 37b of the cathode (porous catalyst) 37 from a power source 43. As a result, CO ２ CO supplied from the gas supply means 34 ２ The gas is electrolyzed as shown in the following formula (4) to produce carbon monoxide gas (CO) and oxygen ions (O ２－ ) occurs. ２ +2e － →CO+O ２－ ...(4)

[0068] The CO gas generated by the above formula (4) is converted into carbon C and CO by thermal decomposition as shown in the following formula (5): ２ Gas is produced. 2CO → C + CO ２ ...(5)

[0069] In this embodiment as well, carbon C generated by the thermal decomposition of CO gas as shown in formula (5) is deposited in the porous region 37a of the cathode 37 (carbon generation step).

[0070] In this embodiment, by switching from the electrolysis mode to the power generation mode of the fuel cell using hydrogen as fuel, H is charged to the one surface 39a of the SOEC 39, which is an example of a solid oxide cell, that is, the cathode (porous catalyst) 37. ２ O gas is supplied, and water vapor (H ２ O) layer Q is formed. As a result of the water vapor layer Q being formed in the porous region 37a of the cathode 37, the deposited carbon C peels off from the porous region 37a due to its own weight every time a certain amount of carbon C is deposited (carbon peeling step).

[0071] As described above, according to the carbon production apparatus 30 of this embodiment, CO ２ Carbon C can be produced by electrolyzing the gas by applying power to the SOEC 39 .

[0072] Then, CO ２By switching to the power generation mode after the gas electrolysis, a water vapor layer Q is formed between the porous body region 37a of the cathode 37 and the carbon C deposited there, and the carbon C intermittently peels off. As a result, the entire porous body region 37a of the cathode 37 is covered with a large amount of deposited carbon C, and the CO ２ The gas electrolysis reaction does not stop in a short time.

[0073] This allows for the CO ２ It is now possible to carry out the gas electrolysis reaction continuously for a long period of time, ２ It is possible to realize a process for continuously producing carbon C from gas efficiently and at low cost with a simple configuration.

[0074] Although the embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention and its equivalents as defined in the claims.

[0075] Although it has been explained that carbon deposited on the surface of the porous catalyst falls off under its own weight, the method for removing the carbon is not limited to this, and it is also possible to place a vibration device using an ultrasonic vibrator or a magnetostrictive vibrator near the carbon and hydrogen production device or the porous catalyst in the carbon production device, and to cause the carbon deposited on the surface of the porous catalyst to fall off by vibration from the vibration device. Of course, instead of placing a vibration device, the porous catalyst may be vibrated and removed by periodically hitting it manually with a hammer or the like.

[0076] (Verification Example 1) In a verification carbon and hydrogen production device corresponding to the second embodiment described above, the anode (porous catalyst) constituting the SOFC cell was made of NiO and Y. ２ O ３ Stabilized ZrO ２An anode (porous catalyst) was formed by dropping an aqueous solution of iron (II) acetate onto a Ni / YSZ porous body containing Ni / YSZ (YSZ) and drying it in a dry oven, and repeating this cycle five times. An EDS image of the Ni / YSZ porous body carrying Fe particles, taken using an energy dispersive X-ray microscope, is shown in Figure 5.

[0077] Using such an anode (porous catalyst), the state of peeling of the produced carbon C from the anode (porous catalyst) was examined at low and high currents. At low currents, the current density was 150 mA / cm. ２ , 70 minutes. At high current, the current density was 150 mA / cm ２ for 25 minutes, followed by a current density of 600 mA / cm ２ The total time was 70 minutes, with each being 45 minutes.

[0078] Then, under each of the above-mentioned conditions, the number of times that carbon C spontaneously peeled off due to the formation of a water vapor layer on the surface of the anode (porous catalyst) was counted within a test time of 70 minutes.

[0079] As a result, carbon C spontaneously peeled off from the anode twice in 70 minutes at low current. Also, carbon C spontaneously peeled off from the anode 10 times in total in 70 minutes at high current. The deposition of the fallen carbon C in the quartz tube after each experiment is shown in Figure 6. According to the results shown in Figure 6, the higher the current density, the more the H ２ It was confirmed that the O gas promotes the formation of a water vapor layer, making carbon peeling more likely to occur.

[0080] (Verification Example 2) Using the verification carbon production apparatus corresponding to the third embodiment shown in Figure 7, the concentration of the iron (II) acetate aqueous solution to be impregnated into the Ni / YSZ porous body was set to a low concentration (0.1 mol / L) and a high concentration (0.6 mol / L), and the amount of Fe particles in the Ni / YSZ porous body was changed.

[0081] Then, CO was emitted using the anode (porous catalyst) at each of the above concentrations. ２The amount and size of carbon C generated on the anode (porous catalyst) by electrolyzing the gas were investigated, and the results are shown in the SEM photographs in Figure 8.

[0082] FIG. 8 confirms that the larger the amount of Fe particles supported on the Ni / YSZ porous body, the larger the amount of carbon produced and the larger the size of the carbon particles produced.

[0083] According to the carbon and / or hydrogen production device and carbon and / or hydrogen production method of the present invention, when a carbon-containing gas is brought into contact with a porous catalyst to produce carbon, it is possible to prevent carbon from accumulating on the porous catalyst and reducing its reactivity. This makes it possible to efficiently produce carbon and / or hydrogen, improve the reaction efficiency of fuel cells, and efficiently decompose carbon dioxide. Therefore, the present invention has industrial applicability.

[0084] 10... Carbon and hydrogen production device 11... Porous catalyst 12... Support 13... H ２ O supply means 14...C ３ H ８ Gas supply means (carbon-containing gas supply means) 15...heating means

Claims

1. A carbon and / or hydrogen production device comprising at least a porous catalyst supporting metal particles, an oxidant supply means for supplying an oxidant to the porous catalyst, and a carbon-containing gas supply means for supplying a carbon-containing gas containing carbon as a constituent element to the porous catalyst, wherein the porous catalyst is formed into a plate shape, and the carbon-containing gas is supplied to one side of the porous catalyst, and the oxidant is supplied to the other side of the porous catalyst.

2. The carbon and / or hydrogen production device according to claim 1, wherein the porous catalyst is formed by supporting the metal particles on a porous body containing an ion-conductive solid oxide.

3. The carbon and / or hydrogen production device according to claim 2, wherein the metal particles contain Fe and / or Co.

4. The oxidizing agent is H ２ O gas and / or O ２ The carbon and / or hydrogen production device according to claim 1 or 2, containing a gas.

5. The carbon-containing gas is a hydrocarbon gas, CO ２ 3. The carbon and / or hydrogen production device according to claim 1, wherein the carbon and / or hydrogen production device comprises at least one of CO.

6. The carbon and / or hydrogen production device according to claim 1 or 2, comprising a solid oxide cell having an anode made of the porous catalyst, a cathode made of a material containing a metal oxide, and a solid electrolyte layer disposed between the anode and the cathode.

7. The carbon and / or hydrogen production device according to claim 6, wherein the anode includes a porous region in which the porous catalyst is formed and a conductive region made of a mesh-shaped conductive material.

8. The carbon and / or hydrogen production device according to claim 6, wherein a hydrocarbon gas and an oxidant are supplied to the solid oxide cell, and electricity is generated between the anode and the cathode.

9. CO ２ Alternatively, CO is supplied, and power is applied between the anode and the cathode to generate CO ２ The carbon and / or hydrogen production device according to claim 6, wherein electrolysis of carbon dioxide or CO is performed.

10. A carbon and / or hydrogen production device comprising: a porous catalyst for producing carbon from a carbon-containing gas containing carbon as a constituent element; and an oxidant layer forming means for forming an oxidant layer on the surface of the porous catalyst, wherein the oxidant layer forming means forms the oxidant layer between the produced carbon and the surface of the porous catalyst when carbon is produced by the porous catalyst.

11. A method for producing carbon and / or hydrogen using the carbon and / or hydrogen production apparatus according to claim 1 or 2, comprising the steps of: supplying hydrocarbons to the porous catalyst and decomposing them into carbon and hydrogen, thereby depositing the carbon on the surface of the porous catalyst; and supplying an oxidant to form an oxidant layer between the surface of the porous catalyst and the deposited carbon, thereby causing the deposited carbon to peel off from the surface of the porous catalyst.

12. A method for producing carbon and / or hydrogen using the carbon and / or hydrogen production device according to claim 6, comprising the steps of: supplying hydrocarbons to the solid oxide cell and decomposing them into carbon and hydrogen, thereby depositing the carbon on the surface of the anode; and supplying an oxidant to form an oxidant layer between the surface of the anode and the deposited carbon, thereby causing the deposited carbon to peel off from the surface of the anode; and the density of the current flowing between the anode and the cathode is 100 mA / cm. ２ The carbon and / or hydrogen production method described above.

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