Electrolytic device

Abstract

To provide an electrolytic device capable of suppressing the lowering of electrolytic efficiency caused by the lowering of a liquid level of an electrolyte in an electrolytic chamber as compared with the conventional one.SOLUTION: An electrolytic device includes an anode part, a cathode part, an electrolytic chamber, an electrolytic solution supply part for supplying an electrolytic solution into the electrolytic chamber, and a discharge part. The electrolytic chamber has a top surface portion and a side surface portion extending downward from the top surface portion. The discharge part is provided at a position lower than the top surface portion and on the side surface portion of the electrolytic chamber. At least one of the anode part and the cathode part can perform a gas generation operation of oxidizing or reducing the electrolytic solution to generate a generated gas. In the gas generation operation, a voltage is applied between the anode part and the cathode part while the electrolytic solution is supplied from the electrolytic solution supply part and the generated gas is discharged together with the electrolytic solution from the discharge part so that the liquid level of the electrolytic solution in the electrolytic chamber is higher than the discharge part and lower than the top surface portion.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an electrolysis device. [Background technology]

[0002] In recent years, electrolysis devices that electrolyze carbon dioxide to produce carbon compounds have been developed in an effort to realize a carbon-neutral society (for example, Patent Document 1). For example, the electrolysis device described in Patent Document 1 is capable of reducing carbon dioxide in an electrolytic solution at a cathode through an electrochemical reaction to produce a reduction product containing a carbon compound. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-25292 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in an electrolysis device that electrolyzes an electrolyte solution as in Patent Document 1, if electrolysis is performed over a long period of time, the electrolyte solution is consumed due to the electrochemical reaction on the electrode parts of the electrolyte solution, and the liquid level drops. Therefore, in conventional electrolysis devices, there is a problem in that the reaction area of ​​the electrolyte solution on the electrode parts decreases, and the electrolysis efficiency drops.

[0005] Therefore, an object of the present invention is to provide an electrolysis device that can suppress a decrease in electrolysis efficiency compared to conventional devices. [Means for solving the problem]

[0006] One aspect of the present invention for solving the above-described problems is an electrolysis device comprising an anode section, a cathode section, an electrolysis chamber, and an electrolyte solution supply section that supplies an electrolytic solution into the electrolysis chamber, the electrolysis chamber having a top surface section, a side surface section extending downward from the top surface section, and a discharge section, the discharge section being located lower than the top surface section and being provided on the side surface section of the electrolysis chamber, and capable of performing a gas generation operation in which the electrolytic solution is oxidized or reduced by at least one of the anode section or the cathode section to generate a generated gas, and in the gas generation operation, the electrolytic solution is supplied from the electrolyte solution supply section so that the liquid level of the electrolytic solution in the electrolysis chamber is higher than the discharge section and lower than the top surface section, while the generated gas is discharged together with the electrolytic solution from the discharge section, and a voltage is applied between the anode section and the cathode section.

[0007] According to this aspect, during gas generation operation, while supplying the electrolyte from the electrolyte supply unit and discharging the generated gas together with the electrolyte from the discharge unit so that the liquid level of the electrolyte in the electrolytic chamber is higher than the discharge unit and lower than the ceiling unit, a voltage is applied between the anode and cathode units. As a result, the liquid level of the electrolyte in the electrolytic chamber does not fall below the lower end of the discharge unit, and the generated gas is also discharged sequentially, thereby suppressing a decrease in electrolysis efficiency due to a drop in the liquid level of the electrolyte in the electrolytic chamber compared to conventional methods.

[0008] In a preferred aspect, the discharge section has suction means for sucking the generated gas and the electrolytic solution, and during the gas generation operation, the suction means sucks the generated gas and the electrolytic solution so that the liquid level of the electrolytic solution does not drop.

[0009] According to this aspect, the produced gas and the electrolyte are forcibly sucked in by the suction means, so that the pressure in the electrolysis chamber is less likely to increase due to the production of the produced gas, and electrolysis can be performed stably.

[0010] In a preferred aspect, the electrolysis chamber has an anode chamber in which the anode section is arranged, the discharge section is provided on a side section of the anode chamber, and the gas generation operation involves decomposing the electrolytic solution in the anode section to generate the generated gas.

[0011] According to this aspect, even when a product gas is produced in the anode section, it is possible to suppress a decrease in electrolysis efficiency due to a drop in the liquid level of the electrolyte in the anode chamber.

[0012] In a preferred aspect, the electrolysis chamber includes an anode chamber in which the anode section is disposed, a cathode chamber in which the cathode section is disposed, and an ion exchange section that divides the anode chamber and the cathode chamber and allows specific ions to pass between the anode chamber and the cathode chamber side, the electrolytic solution supply section that supplies the electrolytic solution into the anode chamber, a second electrolytic solution supply section that supplies a second electrolytic solution into the cathode chamber, the discharge section that discharges the electrolytic solution in the anode chamber and a product gas generated in the anode section, and a second discharge section that discharges the second electrolytic solution in the cathode chamber and a product gas generated in the cathode section, and the discharge section the second discharge unit is provided on a side surface of the anode chamber at a position lower than the ceiling surface of the anode chamber, and the second discharge unit is provided on the side surface of the cathode chamber at a position lower than the ceiling surface of the cathode chamber, and in the gas generating operation, the second electrolytic solution is supplied from the second electrolytic solution supply unit so that the liquid level of the second electrolytic solution in the cathode chamber is higher than the second discharge unit and lower than the ceiling surface of the cathode chamber, while a voltage is applied between the anode unit and the cathode unit while a generated gas generated in the cathode unit is discharged from the second discharge unit together with the second electrolytic solution.

[0013] According to this aspect, the liquid levels of the electrolytic solution and the second electrolytic solution do not drop in either the anode chamber or the cathode chamber, so that a decrease in electrolysis efficiency due to a drop in the liquid levels of the electrolytic solution and the second electrolytic solution can be further suppressed.

[0014] In a preferred aspect, the cathode section is a gas diffusion electrode, and the electrolysis chamber includes an anode chamber in which the anode section is disposed, an ion exchange section that divides the anode chamber and the cathode section and allows specific ions to pass between the anode chamber and the cathode section side, a material gas supply section that supplies a material gas to the cathode section, and a cathode-side gas discharge section that discharges gas that has passed through the cathode section.

[0015] According to this aspect, the material gas can be directly reduced in the cathode section, and the product gas obtained by reduction can be discharged from the cathode-side gas discharge section, so that a high-purity product gas can be obtained.

[0016] In a preferred aspect, the cathode portion is in contact with the ion exchange portion.

[0017] According to this aspect, the source gas can be reduced by the migration of specific ions in the ion exchange section, so that the source gas can be reduced without using an electrolyte on the cathode section side relative to the ion exchange section.

[0018] One aspect of the present invention is an electrolysis device comprising: an anode chamber in which an anode section is disposed; a cathode section; an ion exchange section that divides the anode chamber and the cathode section and allows specific ions to pass between the anode chamber and the cathode section; an electrolyte solution supply section that supplies an electrolytic solution into the anode chamber; an outlet section that discharges the electrolytic solution in the anode chamber and a product gas generated in the anode section; a material gas supply section that supplies a material gas to the cathode section; and a cathode-side gas outlet section that discharges a second product gas generated in the cathode section, wherein the cathode section is in contact with the ion exchange section; and when a voltage is applied between the anode section and the cathode section, the electrolytic solution is decomposed in the anode section to generate a product gas, and the material gas is reduced in the cathode section to generate a second product gas.

[0019] According to this aspect, the material gas can be directly reduced in the cathode section to generate the second product gas, so that an electrolyte is not required for reduction in the cathode section, and a decrease in electrolysis efficiency can be suppressed compared to conventional methods. [Effects of the Invention]

[0020] According to the present invention, the decrease in electrolysis efficiency can be suppressed compared to the conventional case. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a diagram illustrating the principle of operation of an electrolysis device according to a first embodiment of the present invention. [Figure 2]FIG. 4 is a diagram showing the principle of operation of an electrolysis device according to a second embodiment of the present invention. [Figure 3] FIG. 10 is a diagram illustrating the principle of operation of an electrolysis device according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, embodiments of the present invention will be described in detail.

[0023] The electrolysis device 1 of the first embodiment of the present invention mainly produces an oxide gas (first product gas) such as oxygen in the anode section 21, and produces a carbon compound gas (second product gas) from a material gas containing a carbon element such as carbon dioxide in the cathode section 22. As shown in FIG. 1 , the electrolysis device 1 includes an electrolytic cell 2, a first electrolytic solution supply unit 3, an anode-side recovery unit 5, a second electrolytic solution supply unit 6, a cathode-side recovery unit 7, a material gas supply unit 8, a gas supply piping unit 10, and a power supply unit 11.

[0024] (Electrolytic cell 2) As shown in FIG. 1, the electrolytic cell 2 includes a cell main body 20 (electrolysis chamber), an anode section 21, a cathode section 22, an ion exchange section 23, a first electrolytic solution inlet section 25, a first outlet section 26, a second electrolytic solution inlet section 27, and a second outlet section 28.

[0025] As shown in FIG. 1, the tank body 20 is an electrolysis chamber divided by the ion exchange section 23 into a first tank section 30 (anode chamber) and a second tank section 31 (cathode chamber). The first tank section 30 is an anode chamber in which a part or all of the anode section 21 is disposed, and is a storage section that stores the first electrolytic solution 35. The second tank section 31 is a cathode chamber in which a part or all of the cathode section 22 is disposed, and is a storage section that stores the second electrolytic solution .

[0026] The first electrolytic solution 35 is an anolyte that is oxidized by the anode part 21 when current is applied, and an oxide gas (product gas) is generated. The first electrolytic solution 35 is not particularly limited, but may be, for example, water.

[0027] The second electrolytic solution 36 is preferably a liquid capable of dissolving the source gas. The second electrolytic solution 36 is a liquid capable of dissolving the material gas, and serves as a catholyte in which the dissolved material gas is reduced by the cathode section 22 to produce a carbon compound gas (product gas) when current is applied. The second electrolytic solution 36 may be, for example, water.

[0028] As shown in FIG. 1, the tank main body 20 includes a top surface 40, a side surface 41, and a bottom surface . The top surface 40 is a top wall that forms the top surface of the tank main body 20. The side surface portion 41 is a side wall portion that constitutes the side surface of the tank main body portion 20. The side surface portion 41 is a connecting wall portion that connects the top surface portion 40 and the bottom surface portion 42, and extends downward from the top surface portion 40. The bottom surface portion 42 is a bottom wall portion that constitutes the bottom surface of the tank main body portion 20.

[0029] The anode section 21 is disposed in the first tank section 30, and is a section that oxidizes the first electrolytic solution 35 in the first tank section 30 during electrolysis to generate oxide gas.

[0030] The cathode section 22 is disposed in the second tank section 31, and is a section that reduces the material gas (including the material gas dissolved in the second electrolytic solution 36) in the second tank section 31 during electrolysis to generate a cathode reduced gas. The cathode section 22 of this embodiment is capable of reducing carbon dioxide contained in the source gas to generate a carbon compound gas as a cathode reduced gas. The cathode section 22 faces the anode section 21 with the ion exchange section 23 interposed therebetween.

[0031] As shown in FIG. 1, the ion exchange section 23 is a separator that separates the first tank section 30 from the second tank section 31 and is interposed between the anode section 21 and the cathode section 22. The ion exchange section 23 is a film that allows only specific ions (carriers) to move in the thickness direction and restricts the movement of the remaining ions and electrons. The ion exchange section 23 of this embodiment is a cation exchange membrane, which restricts or disables the movement of anions and electrons and allows the movement of only cations.

[0032] The ion exchange section 23 also functions as a blocking film that blocks gas flow in the thickness direction. The ion exchange section 23 is not particularly limited as long as it is capable of ion exchange and does not cause crossover of hydrogen or oxygen, and for example, a polymer membrane such as a membrane of a perfluoroalkylsulfonic acid-based polymer can be used.

[0033] As shown in FIG. 1, the first electrolytic solution introducing section 25 is a section that introduces the first electrolytic solution 35 supplied from the first electrolytic solution supply section 3 into the inside of the first tank section 30. The first electrolytic solution introduction part 25 is provided on the lower end side of the side surface part 41 of the first tank part 30 (on the bottom surface part 42 side).

[0034] The first discharge section 26 is a section that discharges the anode discharge gas containing the first electrolytic solution 35 and the anodization gas generated in the anode section 21 from the inside of the first tank section 30 to the anode-side recovery section 5. First discharge part 26 is provided on the upper end side (top surface part 40 side) of side surface part 41 of first tank part 30, and is provided at a position higher than first electrolytic solution introduction part 25.

[0035] As shown in FIG. 1, second electrolytic solution introducing section 27 is a section that introduces second electrolytic solution 36 supplied from second electrolytic solution supply section 6 into second tank section 31. The second electrolytic solution introduction part 27 is provided on the lower end side of the side surface part 41 of the second tank part 31 (on the bottom surface part 42 side).

[0036] The second discharge section 28 is a section that discharges the second electrolytic solution 36 and the carbide gas generated in the cathode section 22 from the inside of the second tank section 31 to the cathode-side recovery section 7. The second discharge part 28 is provided on the upper end side (top surface part 40 side) of the side surface part 41 of the second tank part 31, and is provided at a position higher than the second electrolytic solution introduction part 27. In this embodiment, the height of the second discharge portion from the bottom surface portion is approximately the same as the height of the first discharge portion from the bottom surface portion .

[0037] (First electrolyte supply section 3) The first electrolytic solution supply section 3 is a section that supplies the first electrolytic solution 35 from the first electrolytic solution introduction section 25 into the first tank section 30, and as shown in Figure 1, it is equipped with a first electrolytic solution supply source 50, a first mixing section 51, and a first pressure-transfer means 52.

[0038] The first electrolytic solution supply source 50 is a supply source capable of supplying fresh first electrolytic solution 35 . The first mixing section 51 is a section that mixes the first electrolytic solution 35 supplied from the first electrolytic solution supply source 50 with the first electrolytic solution 35 separated from the anode exhaust gas in the first separation section 61 of the anode side recovery section 5 described later. First pressure-feeding means 52 is a section that pumps first electrolytic solution 35 mixed in first mixing section 51 toward first electrolytic solution introducing section 25 at a predetermined flow rate. The first pressure-feeding means 52 is not particularly limited as long as it can pressure-feed the first electrolytic solution 35 at a predetermined flow rate, and for example, a pump or the like can be used.

[0039] (Anode side recovery section 5) The anode-side recovery section 5 is a section that recovers the first electrolytic solution 35 and the anode exhaust gas from the first exhaust section 26, and as shown in Figure 1, it is equipped with a first gas recovery section 60, a first separation section 61, and a first suction means 62. The first gas recovery section 60 is a section that recovers the anode exhaust gas. First separation section 61 is a gas-liquid separation section that separates anode exhaust gas and first electrolytic solution 35. The first separation section 61 is capable of supplying part or all of the first electrolytic solution 35 separated from the anode exhaust gas toward the first mixing section 51 of the first electrolytic solution supply section 3, and is capable of supplying part or all of the anode exhaust gas separated from the first electrolytic solution 35 toward the first gas recovery section 60. The first suction means 62 is a part that sucks the first electrolytic solution 35 and anode exhaust gas in the first tank section 30 toward the first separation section 61 so that the liquid level of the first electrolytic solution 35 in the first tank section 30 does not drop. The first suction means 62 is capable of making the pressure inside the first tank portion 30 zero or negative so that the liquid level of the first electrolytic solution 35 does not drop.

[0040] (Second electrolyte supply section 6) The second electrolytic solution supply section 6 is a section that supplies the second electrolytic solution 36 from the second electrolytic solution introduction section 27 into the second tank section 31, and as shown in Figure 1, is equipped with a second electrolytic solution supply source 70, a second mixing section 71, and a second pressure-feeding means 72.

[0041] The second electrolytic solution supply source 70 is a supply source capable of supplying fresh second electrolytic solution 36 . The second mixing section 71 is a section that mixes the second electrolytic solution 36 supplied from the second electrolytic solution supply source 70 with the second electrolytic solution 36 separated from the cathode exhaust gas in the second separation section 81 of the cathode side recovery section 7 described below. Second pressure-feeding means 72 is a section that pumps second electrolytic solution 36 mixed in second mixing section 71 toward second electrolytic solution introducing section 27 at a predetermined flow rate. The second pressure-feeding means 72 is not particularly limited as long as it can pressure-feed the second electrolytic solution 36 at a predetermined flow rate, and for example, a pump or the like can be used.

[0042] (Cathode side recovery section 7) The cathode-side recovery section 7 is a section that recovers the second electrolytic solution 36 and the cathode exhaust gas from the second exhaust section 28, and as shown in FIG. 1, includes a second gas recovery section 80, a second separation section 81, and a second suction means 82. The second gas recovery section 80 is a section that recovers the cathode exhaust gas. The second separation section 81 is a gas-liquid separation section that separates the cathode exhaust gas from the second electrolytic solution . The second separation section 81 is capable of supplying part or all of the second electrolytic solution 36 separated from the cathode exhaust gas toward the second mixing section 71 of the second electrolytic solution supply section 6, and is capable of supplying part or all of the cathode exhaust gas separated from the second electrolytic solution 36 toward the second gas recovery section 80. The second suction means 82 is a part that sucks the second electrolytic solution 36 and cathode exhaust gas in the second tank portion 31 toward the second separation portion 81 so that the liquid level of the second electrolytic solution 36 in the second tank portion 31 does not drop. The second suction means 82 is capable of making the pressure inside the second tank portion 31 zero or negative so that the liquid level of the second electrolytic solution 36 does not drop.

[0043] (Material gas supply unit 8) The source gas supply unit 8 is a part that supplies the source gas to the cathode unit 22 via the gas supply piping unit 10, as shown in FIG.

[0044] (Gas supply piping section 10) The gas supply pipe 10 is a pipe that guides the material gas supplied from the material gas supply unit 8 to the cathode unit 22, and has a material gas outlet disposed near the cathode unit 22 as shown in FIG. Specifically, the gas supply pipe section 10 has a source gas outlet disposed in the vicinity of the lower end of the cathode section 22 .

[0045] (Power supply 11) The power supply device 11 is a power supply device that supplies power to the electrolytic cell 2 and is a voltage application device that applies a voltage between the anode part 21 and the cathode part 22. The power supply device 11 is not particularly limited as long as it can apply a voltage between the anode part 21 and the cathode part 22 . The power supply device 11 may be a commercial power supply device, a power generation device using renewable energy such as a solar cell, or a power storage device such as a secondary battery.

[0046] Next, a gas generating operation for generating an oxide gas and a carbon compound gas using the electrolysis device 1 of this embodiment will be described.

[0047] In the gas generating operation of this embodiment, first, the electrolytic solutions 35, 36 are supplied from the electrolytic solution supply units 3, 6 to the tank units 30, 31, and the tank units 30, 31 are filled with the electrolytic solutions 35, 36 (filling step).

[0048] At this time, the first tank portion 30 is filled with the first electrolytic solution 35, and the anode portion 21 is immersed in the first electrolytic solution 35 inside the first tank portion 30. Similarly, the second tank portion 31 is filled with the second electrolytic solution 36 , and the cathode portion 22 is immersed in the second electrolytic solution 36 in the second tank portion 31 . The liquid levels of the electrolytes 35, 36 are higher than the lower ends of the discharge portions 26, 28 and lower than the top surface portion 40, and spaces 90, 91 are formed between the liquid levels of the electrolytes 35, 36 and the top surface portion 40.

[0049] Next, while supplying the electrolytic solution 35, 36 from the electrolytic solution supply units 3, 6 to the tank units 30, 31, and recovering the electrolytic solution 35, 36 and the gas produced at each electrode unit 21, 22 in the recovery units 5, 7, a voltage is applied between the anode unit 21 and the cathode unit 22 by the power supply unit 11 (application process).

[0050] At this time, in the first electrolytic solution supply unit 3, the first pressure-transfer means 52 pressure-feeds the first electrolytic solution 35 in the first mixing unit 51 into the first tank unit 30 at a predetermined flow rate, and the first electrolytic solution supply unit 3 constantly supplies the first electrolytic solution 35 in the first tank unit 30 so that it overflows and is discharged from the first discharge unit 26 during gas generation operation. In addition, the anode side recovery section 5 uses the first suction means 62 to suck in the first electrolytic solution 35 and the anode exhaust gas so that the volume of the space 90 in the first tank section 30 (the space between the liquid surface of the first electrolytic solution 35 and the top surface section 40) is 10% or more of the amount of oxide gas produced per unit time in the anode section 21. The anode-side recovery section 5 preferably sucks in the first electrolytic solution 35 and the anode exhaust gas so that the volume of the space 90 in the first tank section 30 is 15% or more of the amount of oxide gas produced per unit time, and more preferably sucks in the first electrolytic solution 35 and the anode exhaust gas so that the volume is 20% or more of the amount of oxide gas produced per unit time. The anode side recovery section 5 separates the first electrolytic solution 35 and anode exhaust gas sucked by the first suction means 62 into the first electrolytic solution 35 and the anode exhaust gas using the first separation section 61, supplies the first electrolytic solution 35 to the first mixing section 51, and recovers the anode exhaust gas in the first gas recovery section 60.

[0051] Similarly, in the second electrolytic solution supply unit 6, the second pressure-transfer means 72 pressure-transfers the second electrolytic solution 36 in the second mixing unit 71 so that the amount of supply into the second tank unit 31 is a predetermined flow rate, and the second electrolytic solution supply unit 6 constantly supplies the second electrolytic solution 36 in the second tank unit 31 so that it overflows and is discharged from the second discharge unit 28 during gas generation operation. In addition, the cathode side recovery section 7 uses the second suction means 82 to suck the second electrolytic solution 36 and the cathode exhaust gas so that the volume of the space 91 in the second tank section 31 (the space between the liquid surface of the second electrolytic solution 36 and the top surface section 40) is 10% or more of the amount of carbide gas generated per unit time in the cathode section 22. The cathode side recovery section 7 preferably sucks in the second electrolytic solution 36 and the cathode exhaust gas so that the volume of the space 91 in the second tank section 31 is 15% or more of the amount of carbide gas produced per unit time, and more preferably sucks in the first electrolytic solution 35 and the cathode exhaust gas so that the volume of the space 91 is 20% or more of the amount of carbide gas produced per unit time. The cathode-side recovery unit 7 separates the second electrolytic solution 36 and the cathode exhaust gas sucked by the second suction means 82 into the second electrolytic solution 36 and the cathode exhaust gas by the second separation unit 81, supplies the second electrolytic solution 36 to the second mixing unit 71, and recovers the cathode exhaust gas in the second gas recovery unit 80.

[0052] In this way, in the electrolysis device 1, the supply and discharge amounts are controlled by the suction means 62, 82 of the recovery sections 5, 7 in the tank sections 30, 31 so that the liquid level of the electrolyte 36 exceeds the lower ends of the discharge sections 26, 28 and is stable at a position lower than the top surface section 40, thereby enabling stable electrolysis. The electrolysis device 1 can recover oxide gas as anode exhaust gas by the first gas recovery section 60 of the anode-side recovery section 5, and recover carbon compound gas as cathode exhaust gas by the second gas recovery section 80 of the cathode-side recovery section 7. In the electrolysis device 1, part or all of the electrolyte 35, 36 recovered in the recovery units 5, 7 is returned from the electrolyte supply units 3, 6 to the tank units 30, 31 again for reuse in electrolysis, thereby reducing consumption of the electrolyte 35, 36 compared to conventional methods.

[0053] According to the electrolysis device 1 of this embodiment, in the gas generation operation, the electrolytic solution 35(36) is supplied from the electrolytic solution supply unit 3(6) so that the liquid level of the electrolytic solution 35(36) in the tank unit 30(31) is higher than the discharge unit 26(28) and lower than the top surface unit 40, and a voltage is applied between the anode unit 21 and the cathode unit 22 while the anode exhaust gas (cathode exhaust gas) is discharged from the discharge unit 26(28) together with the electrolytic solution 35(36). Therefore, the liquid level of the electrolytic solution 35(36) in the electrolytic tank 2 does not fall below the lower end of the discharge unit 26(28), and the generated oxide gas (carbon compound gas) is also sequentially discharged. This makes it possible to suppress a decrease in electrolysis efficiency due to a decrease in the liquid level of the electrolytic solution 35(36) in the electrolytic tank 2, compared to conventional methods.

[0054] Furthermore, according to the electrolysis device 1 of this embodiment, the liquid levels of the first electrolytic solution 35 and the second electrolytic solution 36 do not decrease in either the first tank section 30 or the second tank section 31, so that the decrease in electrolysis efficiency due to the decrease in the liquid levels of the first electrolytic solution 35 and the second electrolytic solution 36 can be further suppressed.

[0055] According to the electrolysis device 1 of this embodiment, during the gas generation operation, the suction means 62 (82) sucks the anode exhaust gas (cathode exhaust gas) and the electrolytic solution 35 (36) so that the liquid level of the electrolytic solution 35 (36) does not drop. Therefore, because the suction means 62 (82) forcibly sucks the produced gas and the electrolytic solution 35 (36), the pressure in the tank section 30 (31) is less likely to increase due to the generation of the produced gas, and stable electrolysis can be performed.

[0056] Next, an electrolysis device 100 according to a second embodiment of the present invention will be described. Note that the same components as those in the electrolysis device 1 according to the first embodiment will be denoted by the same reference numerals and will not be described again. The same applies hereinafter.

[0057] As shown in FIG. 2 , the electrolysis device 100 of the second embodiment of the present invention includes an electrolytic cell 102, a first electrolytic solution supply unit 3, an anode-side recovery unit 5, a second electrolytic solution supply unit 6, a cathode-side recovery unit 7, a power supply unit 11, a material gas supply unit 112, and a gas recovery unit 113.

[0058] (Electrolytic cell 102) As shown in FIG. 2, the electrolytic cell 102 includes a cell main body 120, an anode section 21, a cathode section 122, an ion exchange section 23, a first electrolytic solution inlet section 25, a first outlet section 26, a second electrolytic solution inlet section 27, a second outlet section 28, a material gas inlet section 125, and a material gas outlet section 126 (cathode-side gas outlet section).

[0059] The tank body 120 includes a first tank section 30, a second tank section 31, and a material gas tank .

[0060] The material gas tank 124 is a part that constitutes a material gas flow path through which material gas flows from the material gas supply unit 112 toward the gas recovery unit 113 . The material gas tank 124 is capable of passing material gas. The source gas tank 124 has a cathode portion 122 formed on a part of its inner wall in the direction of flow of the source gas (see the arrow in FIG. 2).

[0061] The material gas tank 124 is disposed at a position higher than the second electrolytic solution inlet 27 and lower than the second outlet 28. That is, the material gas tank 124 allows the second electrolytic solution 36 to pass through both the upper and lower sides.

[0062] The cathode section 122 is a gas diffusion electrode that reduces the material gas passing through the material gas tank 124 to produce a carbon compound gas. As shown in FIG. 2, the cathode section 122 is composed of a porous conductive substrate 115 and a catalyst 116, with the catalyst 116 supported on a main surface 117 of the porous conductive substrate 115 facing the ion exchange section 23.

[0063] The material gas inlet 125 is a portion through which the material gas supplied from the material gas supply unit 112 is introduced into the material gas tank . The source gas inlet 125 is provided at a lower position than the second exhaust part .

[0064] The material gas discharge section 126 is a section that discharges material exhaust gas containing the carbon compound gas generated in the cathode section 122 and unreacted material gas from the inside of the material gas tank 124 to the gas recovery section 113. The source gas exhaust part 126 is provided at a position higher than the second electrolytic solution introduction part 27 and lower than the source gas introduction part 125.

[0065] (Material gas supply unit 112) The source gas supply unit 112 is a part that supplies the source gas into the source gas tank 124 .

[0066] (Gas recovery section 113) The gas recovery section 113 is a section that recovers the material exhaust gas generated in the cathode section 122 from the material gas tank 124 .

[0067] Next, a gas generating operation for generating an oxide gas and a carbon compound gas using the electrolysis device 100 of this embodiment will be described.

[0068] In the gas generation operation of this embodiment, first, the electrolytic solution 35, 36 is supplied from the electrolytic solution supply section 3, 6 to the tank section 30, 31, and the electrolytic solution 35, 36 is filled up to the height of the discharge section 26, 28 in the tank section 30, 31, and then the material gas is supplied from the material gas supply section 112 into the material gas tank 124 (filling process).

[0069] Then, while the electrolyte solutions 35, 36 are supplied from the electrolyte solution supply units 3, 6 to the tank units 30, 31, the electrolyte solutions 35, 36 and each exhaust gas are recovered from the recovery units 5, 7, and the material gas is circulated through the material gas tank 124 from the material gas supply unit 112 side toward the gas recovery unit 113 side, and a voltage is applied between the anode unit 21 and the cathode unit 122 by the power supply unit 11 (application process).

[0070] At this time, a portion of the carbon compound gas generated in the cathode section 122 flows into the second tank section 31 and is recovered in the cathode side recovery section 7 together with the second electrolytic solution 36, and the remainder is recovered in the gas recovery section 113 together with the unreacted material gas.

[0071] According to the electrolysis device 100 of this embodiment, a material gas flow path is configured from the material gas supply unit 112 to the gas recovery unit 113 via the material gas tank 124, so that fresh material gas can be exposed to the cathode unit 122 without being blocked by unreacted material gas, thereby improving the reaction efficiency compared to conventional methods.

[0072] Next, an electrolysis device 200 according to a third embodiment of the present invention will be described.

[0073] An electrolysis device 200 according to a third embodiment of the present invention includes an electrolytic cell 202, a first electrolytic solution supply unit 3, an anode-side recovery unit 5, a material gas supply unit 112, and a gas recovery unit 113, as shown in FIG.

[0074] (Electrolytic cell 202) As shown in Figure 3, the electrolytic cell 202 includes a cell main body 220, an anode section 21, a cathode section 122, an ion exchange section 23, a first electrolytic solution introduction section 25, a first discharge section 26, a material gas introduction section 125, and a material gas discharge section 126, and the surface of the cathode section 122 facing the catalyst 116 is in direct contact with the ion exchange section 23.

[0075] The tank body 220 includes a first tank 30 and a material gas tank 124, and differs from the tank body 120 of the second embodiment in that the second tank 31 is not provided.

[0076] Next, a gas generating operation for generating an oxide gas and a carbon compound gas using the electrolysis device 200 of this embodiment will be described.

[0077] In the gas generation operation of this embodiment, first, the first electrolytic solution 35 is supplied from the first electrolytic solution supply unit 3 to the first tank unit 30, and the first electrolytic solution 35 is filled up to the height of the discharge unit 26 in the first tank unit 30, and then the material gas is supplied from the material gas supply unit 112 into the material gas tank 124 (filling process).

[0078] Then, while the first electrolytic solution 35 is supplied from the first electrolytic solution supply unit 3 to the first tank unit 30, the first electrolytic solution 35 and the anode exhaust gas generated in the anode unit 21 are recovered from the anode side recovery unit 5, and the material gas is circulated through the material gas tank 124 from the material gas supply unit 112 side toward the gas recovery unit 113 side, and a voltage is applied between the anode unit 21 and the cathode unit 122 by the power supply device 11 (application process).

[0079] According to the electrolysis device 200 of this embodiment, the entire amount of carbon compound gas generated in the cathode section 122 can be recovered as a material exhaust gas in the gas recovery section 113, so that the carbon compound gas can be recovered efficiently.

[0080] According to the electrolysis device 200 of this embodiment, the material exhaust gas containing the carbon compound gas can be collected from the material gas discharge portion 126 without using the second electrolytic solution 36, and therefore the carbon compound gas can be produced at low cost.

[0081] In the embodiment described above, the first electrolytic solution 35 and the anode exhaust gas are separated in the first separation section 61 of the anode-side recovery section 5, and the first electrolytic solution 35 is supplied to the first electrolytic solution supply section 3 for reuse, but the present invention is not limited to this. The first electrolytic solution 35 and the anode exhaust gas do not have to be separated in the first separation section 61 of the anode-side recovery section 5, and the first electrolytic solution 35 does not have to be reused. Similarly, the second electrolytic solution 36 and the cathode exhaust gas are separated in the second separation section 81 of the cathode-side recovery section 7, and the second electrolytic solution 36 is supplied to the second electrolytic solution supply section 6 for reuse, but the present invention is not limited to this. It is also possible that the second electrolytic solution 36 and the cathode exhaust gas are separated in the second separation section 81 of the cathode-side recovery section 7, and the second electrolytic solution 36 does not have to be reused.

[0082] In the above-described embodiment, gas is generated in both the anode section 21 and the cathode section 22, but the present invention is not limited to this. Gas may be generated in only one of the electrode sections, the anode section 21 and the cathode section 22. For example, an oxide gas may be generated in the anode section 21 and a solid or liquid carbon compound may be generated in the cathode section 22, or a solid or liquid oxide may be generated in the anode section 21 and a carbon compound gas may be generated in the cathode section 22.

[0083] In the above-described embodiment, the first electrolytic solution 35 is interposed between the anode portion 21 and the ion exchange portion 23, but the present invention is not limited to this, and the anode portion 21 and the ion exchange portion 23 may be in direct contact with each other.

[0084] In the first embodiment described above, the source gas supply unit 8 is provided as a source of the source gas, but the present invention is not limited to this. If the source gas is soluble in the second electrolytic solution 36, the source gas may be dissolved in the second electrolytic solution 36 in advance and supplied from the second electrolytic solution supply unit 6 into the second tank 31, and the source gas supply unit 8 may be omitted.

[0085] In the first and second embodiments described above, the liquid levels of the electrolytes 35, 36 are controlled so as not to drop due to the suction of the suction means 62, 82, but the present invention is not limited to this. The liquid levels of the electrolytes 35, 36 may also be controlled so as not to drop due to the amount of pressure being applied to the electrolytes 35, 36 by the pressure-feed means 52, 72.

[0086] In the first and second embodiments described above, the discharge portions 26, 28 are at the same height, and the electrolytes 35, 36 are overflowed and discharged from the discharge portions 26, 28 in both the first tank portion 30 and the second tank portion 31, but the present invention is not limited to this. The discharge portions 26, 28 may be at different heights, and the electrolytes 35, 36 may be overflowed and discharged from the discharge portions 26, 28 in only one of the first tank portion 30 and the second tank portion 31.

[0087] In the second embodiment described above, a gas diffusion electrode is used for the cathode section 122, but the present invention is not limited to this. A gas diffusion electrode may also be used for the anode section 21.

[0088] In the above-described embodiments, each component can be freely substituted or added between the respective embodiments as long as it falls within the technical scope of the present invention. [Explanation of symbols]

[0089] 1,100,200 Electrolyzer 3 First electrolyte supply section 6 Second electrolyte supply section 8. Material gas supply section 20,120,220 Tank body (electrolysis chamber) 21 Anode part 22,122 Cathode 23 Ion exchange unit 26 1st discharge section 28 2nd discharge section 30 1st tank section (anode chamber) 31 Second tank section (cathode chamber) 35 First electrolyte 36 Second electrolyte 40 Top section 41 Side part 62 First suction means 82 Second suction means 112 Material gas supply unit 126 Material gas exhaust section (cathode side gas exhaust section)

Claims

1. The electrolytic cell has an anode section, a cathode section, an electrolytic chamber, and an electrolytic solution supply section that supplies an electrolytic solution into the electrolytic chamber, the electrolysis chamber has a top surface portion, a side surface portion extending downward from the top surface portion, and a discharge portion; the discharge portion is located at a position lower than the top surface portion and is provided on a side surface portion of the electrolysis chamber, a gas generating operation can be performed by oxidizing or reducing the electrolytic solution in at least one of the anode section or the cathode section to generate a generated gas; In the gas generating operation, the electrolytic device supplies the electrolytic solution from the electrolytic solution supply unit so that the liquid level of the electrolytic solution in the electrolytic chamber is higher than the discharge unit and lower than the top surface unit, while discharging the generated gas together with the electrolytic solution from the discharge unit.

2. the exhaust unit has a suction means for sucking the generated gas and the electrolytic solution, 2. The electrolysis device according to claim 1, wherein in the gas generating operation, the generated gas and the electrolytic solution are sucked by the suction means so that the liquid level of the electrolytic solution does not drop.

3. the electrolysis chamber has an anode chamber in which the anode part is disposed, the discharge portion is provided on a side surface of the anode chamber, The electrolysis device according to claim 1 , wherein the gas generating operation generates the generated gas by decomposing the electrolytic solution in the anode section.

4. the electrolysis chamber includes an anode chamber in which the anode section is disposed, a cathode chamber in which the cathode section is disposed, and an ion exchange section that divides the anode chamber and the cathode chamber and allows specific ions to pass between the anode chamber and the cathode chamber, the electrolytic solution supply unit that supplies the electrolytic solution into the anode chamber, the second electrolytic solution supply unit that supplies a second electrolytic solution into the cathode chamber, the discharge unit that discharges the electrolytic solution in the anode chamber and a product gas generated in the anode section, and a second discharge unit that discharges the second electrolytic solution in the cathode chamber and a product gas generated in the cathode section, the discharge portion is provided on a side surface of the anode chamber at a position lower than a ceiling surface of the anode chamber, the second discharge portion is provided on a side surface portion of the cathode chamber at a position lower than a top surface portion of the cathode chamber, 2. The electrolysis device according to claim 1, wherein in the gas generating operation, a voltage is applied between the anode unit and the cathode unit while the second electrolytic solution is supplied from the second electrolytic solution supply unit so that a liquid level of the second electrolytic solution in the cathode chamber is higher than the second discharge unit and lower than a ceiling portion of the cathode chamber, and while the second electrolytic solution and a generated gas generated in the cathode unit are discharged from the second discharge unit.

5. the cathode portion is a gas diffusion electrode, 5. The electrolysis device according to claim 1, wherein the electrolysis chamber comprises an anode chamber in which the anode section is disposed, an ion exchange section that divides the anode chamber and the cathode section and allows specific ions to pass between the anode chamber and the cathode section side, a material gas supply section that supplies a material gas to the cathode section, and a cathode-side gas discharge section that discharges the gas that has passed through the cathode section.

6. The electrolysis device according to claim 5 , wherein the cathode portion is in contact with the ion exchange portion.

7. an anode chamber in which an anode unit is disposed; A cathode portion; an ion exchange section that divides the anode chamber and the cathode section and allows specific ions to pass between the anode chamber and the cathode section; an electrolyte supply unit that supplies an electrolyte into the anode chamber; an exhaust section that exhausts the electrolytic solution in the anode chamber and a product gas generated in the anode section; a source gas supply unit that supplies a source gas to the cathode unit; a cathode-side gas discharge section that discharges a second product gas generated in the cathode section, the cathode portion is in contact with the ion exchange portion, an electrolysis device, wherein a voltage is applied between the anode section and the cathode section, whereby the electrolytic solution is decomposed in the anode section to generate a product gas, and the material gas is reduced in the cathode section to generate a second product gas.

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