Electrolysis equipment

Abstract

The present invention provides an electrolytic apparatus that can suppress the decrease in electrolytic efficiency caused by liquid generation compared to conventional devices. [Solution] The device comprises a gas diffusion electrode section, a counter electrode section, an electrolysis chamber, a gas chamber, a gas supply section, and a gas recovery section. The gas diffusion electrode section has a first main surface and a second main surface, the first main surface being exposed to the gas chamber and the second main surface facing the counter electrode section. The gas diffusion electrode section can generate a liquid by reducing or oxidizing a material gas by applying a voltage between it and the counter electrode section. The gas chamber has a liquid inlet at a position lower than the first main surface of the gas diffusion electrode section when the first main surface of the gas diffusion electrode section is viewed from the front, into which liquid flows from the gas diffusion electrode section. The gas supply section is configured to supply the material gas from a position that does not overlap with the gas diffusion electrode section when the first main surface of the gas diffusion electrode section is viewed from the front, and from a position different from the gas recovery position of the gas recovery section.

Description

Technical Field

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

Background Art

[0002] In recent years, in order to achieve a carbon-neutral society, an electrolysis device that electrolyzes carbon dioxide to produce a carbon compound has been developed (for example, Patent Document 1). For example, in the electrolysis device described in Patent Document 1, by an electrochemical reaction, it is possible to reduce carbon dioxide at the cathode and generate a reduction product containing a carbon compound. [[ID=)15]]

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the electrolysis device of Patent Document 1, when reducing carbon dioxide, in addition to the carbon compound as the main product, water is generated as a by-product, and the water seeps out to the gas flow path side of the gas diffusion electrode. Therefore, when operating for a long time, the water on the gas diffusion electrode drops by gravity and accumulates at the bottom, gradually blocking the gas input port for supplying carbon dioxide, blocking the material gas, and causing a problem of reduced electrolysis efficiency.

[0005] Therefore, an object of the present invention is to provide an electrolysis device that can suppress a decrease in electrolysis efficiency caused by the generation of a liquid as compared with the prior art.

Means for Solving the Problems

[0006] One aspect of the present invention for solving the above-mentioned problems is an electrolytic device comprising a gas diffusion electrode section, a counter electrode section, an electrolytic chamber, a gas chamber, a gas supply section for supplying a material gas to the inside of the gas chamber, and a gas recovery section for recovering the gas from the gas chamber, wherein the gas diffusion electrode section has a first main surface and a second main surface, the first main surface being exposed to the gas chamber and the second main surface facing the counter electrode section, the gas diffusion electrode section is capable of reducing or oxidizing the material gas to produce a liquid by applying a voltage to the counter electrode section, the gas chamber is provided with a liquid inlet at a position lower than the first main surface of the gas diffusion electrode section when the first main surface of the gas diffusion electrode section is viewed from the front, into which the liquid flows from the gas diffusion electrode section, and the gas supply section is capable of supplying the material gas from a position that does not overlap with the gas diffusion electrode section when the first main surface of the gas diffusion electrode section is viewed from the front, and from a position different from the gas recovery position by the gas recovery section.

[0007] In this configuration, the liquid generated in the gas diffusion electrode flows into the liquid inlet, which is located at a lower position than the gas diffusion electrode. As a result, the liquid is less likely to remain on the gas diffusion electrode, and the supply of material gas to the gas diffusion electrode is less likely to be obstructed by the liquid. According to this configuration, the gas supply unit is located in a position that does not overlap with the gas diffusion electrode unit, and the material gas is not supplied from the gas supply unit to the gas diffusion electrode unit in a manner that causes direct collision. As a result, the material gas can be supplied evenly to the gas diffusion electrode unit, and the distribution of the material gas exposed on the first main surface of the gas diffusion electrode unit is less likely to become large.

[0008] A preferred configuration is that the gas recovery unit can recover gas from the gas chamber from a position that does not overlap with the gas diffusion electrode when the first main surface of the gas diffusion electrode is viewed from the front.

[0009] A preferred configuration is that the gas supply unit is capable of supplying the material gas to a position higher than the center of the gas diffusion electrode unit, and the gas recovery unit is capable of recovering the gas in the gas chamber from a position lower than the supply position of the material gas from the gas supply unit.

[0010] A preferred configuration includes a gas flow path connecting the gas supply section through the gas chamber to the gas recovery section, the liquid inlet is formed in the middle of the gas flow path, and the gas recovery section is capable of recovering the liquid along with the gas from the liquid inlet.

[0011] A preferred configuration further includes a liquid recovery unit that recovers the liquid from the liquid inlet, separate from the gas recovery unit.

[0012] A preferred configuration is in which the gas diffusion electrode portion comprises a substrate and a catalyst layer, the catalyst layer being formed on the second main surface side of the substrate.

[0013] The aspects described above can be dependent on each other, refer to some of their components, or substitute for some of their components, as long as they fall within the technical scope of the present invention. [Effects of the Invention]

[0014] According to the present invention, the decrease in electrolysis efficiency caused by liquid generation can be suppressed compared to conventional methods. [Brief explanation of the drawing]

[0015] [Figure 1] This is a schematic diagram illustrating the operating principle of an electrolytic device according to the first embodiment of the present invention, where (a) is a cross-sectional view and (b) is a cross-sectional view at a different location than (a). [Figure 2] Figure 1 is a cross-sectional perspective view of the electrolytic apparatus. [Figure 3] This is a schematic diagram illustrating the operating principle of an electrolytic device according to a second embodiment of the present invention, where (a) is a cross-sectional view and (b) is a cross-sectional view at a different location than (a). [Figure 4] This is a schematic diagram illustrating the operating principle of an electrolytic device according to another embodiment of the present invention, where (a) is an embodiment comprising a gas induction section and a liquid induction section, and (b) is an embodiment in which the bottom surface slopes downward toward the third discharge section. [Modes for carrying out the invention]

[0016] Hereinafter, embodiments of the present invention will be described in detail.

[0017] The electrolyzer 1 of the first embodiment of the present invention mainly produces oxide gases such as oxygen in the anode part 21 (counter electrode part), and produces carbon compound gases from material gases containing carbon elements such as carbon dioxide in the cathode part 22 (gas diffusion electrode part), and generates a liquid 15 as a by-product in the cathode part 22. As shown in FIG. 1, the electrolyzer 1 includes an electrolytic cell 2, a first electrolytic solution supply unit 3, a first recovery unit 5, a second electrolytic solution supply unit 6, a second recovery unit 7, a material gas supply unit 8 (gas supply unit), a third recovery unit 10 (gas recovery unit), and a power supply device 11.

[0018] <Electrolytic cell 2> As shown in FIG. 1, the electrolytic cell 2 includes a cell body part 2, an anode part 21, a cathode part 22, an ion exchange part 23, a first electrolytic solution introduction part 24, a first discharge part 25, a second electrolytic solution introduction part 26, a second discharge part 27, a material gas introduction part 28, and a third discharge part 29.

[0019] (Cell body part 20) As shown in FIG. 1, the cell body part 20 is an electrolytic chamber partitioned into a first cell part 30 and a second cell part 31 by the ion exchange part 23.

[0020] The first cell part 30 is an anode chamber in which part or all of the anode part 21 is arranged. The first cell part 30 is a housing part that houses the first electrolytic solution 35, and constitutes a first electrolytic solution flow path through which the first electrolytic solution 35 flows from the first electrolytic solution introduction part 24 toward the first discharge part 25.

[0021] The second cell part 31 is a cathode chamber in which part or all of the cathode part 22 is arranged, and is partitioned into an electrolytic solution chamber 32 and a gas chamber 33 by the cathode part 22. The electrolytic solution chamber 32 is a housing part that houses the second electrolytic solution 36, and constitutes a second electrolytic solution flow path through which the second electrolytic solution 36 flows from the second electrolytic solution introduction part 26 toward the second discharge part 27. The gas chamber 33 is a containment section for material gas and constitutes a gas flow path 37 through which the material gas flows from the material gas introduction section 28 toward the third discharge section 29.

[0022] The first electrolyte 35 is an anodic solution that is oxidized by the anode 21 when an electric current is applied, generating an oxide gas (product gas). The first electrolyte 35 is not particularly limited, but for example, water, acidic aqueous solutions such as sulfuric acid aqueous solution or potassium chloride aqueous solution, or alkaline aqueous solutions such as potassium hydroxide aqueous solution or potassium bicarbonate aqueous solution can be used.

[0023] The second electrolyte 36 is preferably a liquid capable of dissolving the material gas. The second electrolyte 36 is a liquid capable of dissolving material gases, and when an electric current is applied, the material gas dissolved by the cathode 22 is reduced, and a carbon compound gas (product gas) is generated. The second electrolyte 36 is not particularly limited, but for example, water, acidic aqueous solutions such as sulfuric acid aqueous solution or potassium chloride aqueous solution, or alkaline aqueous solutions such as potassium hydroxide aqueous solution or potassium bicarbonate aqueous solution can be used.

[0024] As shown in Figure 1, the tank body 20 includes a top surface 40, side surfaces 41, a bottom surface 42, and partition walls 43. The top surface portion 40 is the top wall portion that constitutes the top surface of the tank body portion 20. The side portion 41 is a side wall portion that constitutes the side of the tank body portion 20. The side portion 41 is a connecting wall that connects the top portion 40 and the bottom portion 42, and extends downward from the top portion 40. The bottom portion 42 is the bottom wall portion that constitutes the bottom surface of the tank body portion 20. The partition wall 43 supports the cathode 22 and, together with the cathode 22, is a vertical wall that partitions the electrolyte chamber 32 and the gas chamber 33. As shown in Figure 1(b), the partition wall 43 comprises an upper wall 44 located above the cathode 22 and a lower wall 45 located below it. The upper wall section 44 is a vertical wall section that hangs down from the top surface section 40, and the lower wall section 45 is a vertical wall section that rises upward from the bottom surface section 42.

[0025] (Anode section 21) The anode section 21 is located within the first tank section 30 and, during electrolysis, oxidizes the first electrolyte 35 within the first tank section 30, generating oxide gas.

[0026] (Cathode section 22) The cathode section 22 is located at the boundary between the electrolyte chamber 32 and the gas chamber 33 of the second cell section 31. During electrolysis, it reduces the material gas in the gas chamber 33 or the material gas dissolved in the second electrolyte 36 to generate cathode reduction gas, and also reduces a portion of the second electrolyte 36 as a by-product to produce liquid 15. The cathode 22 of this embodiment is capable of reducing carbon dioxide contained in the material gas to produce a carbon compound gas, which is a cathode reduction gas, and water, which is a liquid 15. Furthermore, when a carbon compound gas dissolves in water, liquid 15 is an aqueous solution of the carbon compound in which the carbon compound is dissolved in water.

[0027] The cathode portion 22 is a gas diffusion electrode portion having a first main surface 52 and a second main surface 53, and a catalyst layer 51 is formed on the substrate 50. In the cathode section 22, the catalyst layer 51 is located on the ion exchange section 23 side relative to the substrate 50, and it faces the anode section 21 with the ion exchange section 23 in between. The base material 50 is a porous base material having multiple pores, which allows gas to pass through in the thickness direction. The catalyst layer 51 is not particularly limited as long as it can reduce carbon dioxide contained in the material gas and produce carbon compounds. For example, metal catalysts such as zinc, palladium, silver, and gold that can reduce carbon dioxide to C1 compounds such as carbon monoxide, methane, and methanol, or metal catalysts such as copper that can reduce carbon dioxide to C2 compounds such as ethane, ethylene, and ethanol can be used.

[0028] (Ion exchange unit 23) As shown in Figure 1, the ion exchange section 23 is a separator that separates the first tank section 30 and 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 membrane that, by impregnating it with water from the electrolytes 35 and 36, allows only specific ions (carriers) to move in the thickness direction, while restricting the movement of other ions and electrons. The ion exchange section 23 in this embodiment is a cation exchange membrane that restricts or prevents the movement of anions and electrons, allowing only cations to move. The ion exchange section 23 may also be an anion exchange membrane that restricts or prevents the movement of cations and electrons, allowing only anions to move.

[0029] Furthermore, the ion exchange section 23 also serves as a barrier film that blocks the flow of gas in the thickness direction. The ion exchange section 23 is not particularly limited as long as it is capable of ion exchange and hydrogen and oxygen do not cross over; for example, a polymer membrane such as a perfluoroalkyl sulfonic acid polymer membrane can be used.

[0030] (First electrolyte introduction part 24) As shown in Figure 1, the first electrolyte introduction section 24 is the part that introduces the first electrolyte 35 supplied from the first electrolyte supply section 3 into the first tank section 30. The first electrolyte introduction section 24 is located on the lower end side (bottom side 42 side) of the side surface 41 of the first tank section 30.

[0031] (1st discharge section 25) The first discharge section 25 is a part that discharges the first electrolyte 35 from inside the first tank section 30 to the first recovery section 5, and also discharges the anode exhaust gas containing oxide gas generated in the anode section 21. The first discharge section 25 is located on the upper end side (top surface 40 side) of the side surface 41 of the first tank section 30, and is positioned higher than the first electrolyte introduction section 24.

[0032] (Second electrolyte introduction section 26) The second electrolyte introduction section 26, as shown in Figure 1, is the part that introduces the second electrolyte 36 supplied from the second electrolyte supply section 6 into the second cell section 31. The second electrolyte introduction section 26 is located on the lower end side (bottom side 42 side) of the side surface 41 of the second tank section 31.

[0033] (Second discharge section 27) The second discharge section 27 is a part that discharges the second electrolyte 36 from inside the electrolyte chamber 32 to the second recovery section 7, and also discharges the first cathode exhaust gas, which contains carbide gas, a cathode reduction gas generated in the cathode section 22. The second discharge section 27 is located on the upper end side (top surface 40 side) of the side surface 41 of the second tank section 31, and is positioned higher than the second electrolyte introduction section 26. As shown in Figure 2, the height of the second discharge section 27 from the bottom surface 42 is approximately the same as the height of the first discharge section 25 from the bottom surface 42.

[0034] (Material gas introduction section 28) As shown in Figure 1, the material gas introduction section 28 is the part that introduces the material gas supplied from the material gas supply section 8 into the second tank section 31. The material gas introduction section 28 is located on the upper end side (top surface side 40 side) of the side surface 41 of the second tank section 31. In this embodiment, the material gas introduction section 28 is positioned at a height from the bottom surface 42 that is approximately the same as the height from the bottom surface 42 of the second discharge section 27, as shown in Figure 2.

[0035] (Third discharge section 29) The third discharge section 29 is a part that discharges the material gas residue (unreacted material gas) and the second cathode exhaust gas, which includes the carbide gas generated in the cathode section 22, from inside the gas chamber 33 to the third recovery section 10. In this embodiment, the third discharge unit 29 discharges the liquid 15 generated in the cathode unit 22 to the third recovery unit 10, in addition to the second cathode exhaust gas. The third discharge section 29 is located on the lower end side (bottom surface 42 side) of the side surface 41 of the second tank section 31, and is positioned lower than the material gas introduction section 28.

[0036] Here, we will explain the positional relationships of the various components that make up the electrolytic cell 2.

[0037] As shown in Figure 2, the material gas introduction section 28 and the third discharge section 29 are provided in positions that do not overlap with the cathode section 22 when the first main surface 52 of the cathode section 22 is viewed from the front. In other words, the material gas introduction section 28 and the third discharge section 29 are not facing the cathode section 22, but are provided at positions offset from the cathode section 22 in the direction of expansion of the cathode section 22. The material gas introduction section 28 is positioned opposite the upper wall section 44 of the partition wall section 43 with a gap between them, and the third discharge section 29 is positioned opposite the lower wall section 45 of the partition wall section 43 with a gap between them. As shown in Figure 2, the material gas introduction section 28 is located higher than the catalyst layer 51 of the cathode section 22, and the third discharge section 29 is located lower than the catalyst layer 51 of the cathode section 22.

[0038] As shown by the arrow in Figure 1(b), the electrolytic cell 2 has a gas inlet 46 formed near the corner between the top surface 40 and the upper wall 44, where the material gas introduced from the material gas introduction section 28 collides with the upper wall 44. In other words, the material gas introduced from the material gas introduction section 28 collides with the upper wall 44, changes direction, and is supplied to the cathode section 22 via the gas inlet 46.

[0039] In the electrolytic cell 2, the first main surface 52 of the cathode section 22 on the gas chamber 33 side is flush with the gas chamber 33 side surface of the lower wall section 45, or protrudes further toward the gas chamber 33 side than the gas chamber 33 side surface of the lower wall section 45. A liquid inlet 47 is formed near the corner between the bottom surface section 42 and the lower wall section 45, through which the liquid 15 flows from the cathode section 22 down the lower wall section 45. That is, the liquid 15 generated in the cathode section 22 falls into the liquid inlet 47 and is then recovered from the third recovery section 10 together with the second cathode exhaust gas.

[0040] <First electrolyte supply section 3> The first electrolyte supply unit 3 is the part that supplies the first electrolyte 35 from the first electrolyte introduction unit 24 into the first tank unit 30.

[0041] <First Recovery Section 5> The first recovery unit 5 is a part that recovers the first electrolyte 35 and anode exhaust gas from the first discharge unit 25.

[0042] <Second electrolyte supply section 6> The second electrolyte supply unit 6 is the part that supplies the second electrolyte 36 into the electrolyte chamber 32 from the second electrolyte introduction unit 26.

[0043] <Second Recovery Section 7> The second recovery unit 7 is a part that recovers the second electrolyte 36 and cathode exhaust gas from the second discharge unit 27.

[0044] <Material Gas Supply Unit 8> As shown in Figure 1, the material gas supply unit 8 is the part that supplies material gas from the material gas introduction unit 28 into the gas chamber 33.

[0045] <Third Recovery Section 10> The third recovery unit 10 is a part that recovers the second cathode exhaust gas and liquid 15 from the third discharge unit 29.

[0046] <Power supply device 11> The power supply unit 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 unit 21 and the cathode unit 22. The power supply unit 11 is not particularly limited as long as it can apply voltage between the anode unit 21 and the cathode unit 22. The power supply device 11 may be a commercial power supply device, a power generation device using renewable energy such as solar cells, or an energy storage device such as a secondary battery.

[0047] Next, we will describe the gas generation operation that generates oxide gas and carbon compound gas using the electrolytic device 1 of this embodiment.

[0048] In the gas generation operation of this embodiment, first, electrolytes 35 and 36 are supplied from the electrolyte supply units 3 and 6 to the tank units 30 and 31, filling the tank units 30 and 31 with electrolytes 35 and 36 up to the height of the discharge units 25 and 27, and then material gas is supplied from the material gas supply unit 8 into the gas chamber 33 (filling process).

[0049] Then, electrolytes 35 and 36 are supplied from the electrolyte supply units 3 and 6 to the tank units 30 and 31, while the electrolytes 35 and 36 and each exhaust gas are recovered from the recovery units 5 and 7. Furthermore, material gas is circulated into the gas chamber 33 from the material gas supply unit 8 side toward the third recovery unit 10 side, and a voltage is applied between the anode unit 21 and the cathode unit 22 by the power supply unit 11 (voltage application step).

[0050] At this time, some of the carbon compound gas generated in the cathode section 22 flows into the electrolyte chamber 32 and dissolves in the second electrolyte 36, or accumulates near the top surface 40 of the electrolyte chamber 32 and is recovered as the first cathode exhaust gas in the second recovery section 7 along with the second electrolyte 36, while the remainder flows into the gas chamber 33 and is recovered as the second cathode exhaust gas in the third recovery section 10 along with the unreacted material gas. In addition, the liquid 15 generated in the cathode section 22 flows down the lower wall 45 into the liquid inlet 47 and is then recovered together with the second cathode exhaust gas from the third discharge section 29 to the third recovery section 10. Meanwhile, the oxide gas generated in the anode section 21 either dissolves in the first electrolyte 35 or accumulates near the top surface 40 of the first tank section 30, and is recovered from the first discharge section 25 together with the first electrolyte 35 as anode exhaust gas in the first recovery section 5.

[0051] According to the electrolytic apparatus 1 of this embodiment, the cathode 22 has a first main surface 52 and a second main surface 53, the first main surface 52 is exposed to the gas chamber 33 and the second main surface 53 faces the anode 21, and the cathode 22 can reduce the material gas and produce a carbon compound gas and liquid 15 by applying a voltage between the cathode 22 and the anode 21. In other words, since carbon dioxide can be reduced to produce a carbon compound gas according to the electrolytic apparatus 1, carbon dioxide can be used as a carbon material. According to the electrolytic apparatus 1 of this embodiment, the gas chamber 33 is provided with a liquid inlet 47 at a position lower than the first main surface 52 of the cathode 22 when the first main surface 52 of the cathode 22 is viewed from the front, into which the liquid 15 flows from the cathode 22. That is, since the liquid 15 generated in the cathode 22 flows into the liquid inlet 47 at a position lower than the cathode 22, the liquid 15 is less likely to remain on the cathode 22, and the supply of material gas to the cathode 22 is less likely to be obstructed by the liquid 15. According to the electrolytic apparatus 1 of this embodiment, the material gas supply unit 8 can supply material gas from a position that does not overlap with the cathode unit 22 when the first main surface 52 of the cathode unit 22 is viewed from the front, and from a position different from the third discharge unit 29, which is the gas collection position by the third recovery unit 10. In other words, since the material gas is not supplied from the material gas supply unit 8 in such a way that it directly collides with the cathode unit 22, the material gas can be supplied evenly to the cathode unit 22, and the distribution of material gas on the first main surface 52 of the cathode unit 22 is less likely to become large.

[0052] In the electrolytic device 1 of this embodiment, it is preferable that the third recovery unit 10 can recover gas from the gas chamber 33 from a position that does not overlap with the cathode unit 22 when the first main surface 52 of the cathode unit 22 is viewed from the front. That is, it is preferable that the third recovery unit 10 recovers material gas from the third discharge unit 29 outside the cathode unit 22. This allows the material gas to flow more evenly into the cathode unit 22.

[0053] In the electrolytic apparatus 1 of this embodiment, it is preferable that the material gas supply unit 8 can supply material gas to a position higher than the center of the cathode unit 22, and that the third recovery unit 10 can recover gas from the gas chamber 33 from a position lower than the supply position of material gas from the material gas supply unit 8. In this way, the flow of material gas can be used to make the liquid 15 flow into the liquid inlet 47.

[0054] In the electrolytic apparatus 1 of this embodiment, there is a gas flow path 37 that connects from the material gas supply unit 8 through the gas chamber 33 to the third recovery unit 10, and the liquid inlet 47 is formed in the middle of the gas flow path 37, and it is preferable that the third recovery unit 10 can recover the liquid 15 together with the gas in the gas chamber 33 from the liquid inlet 47. This makes it easy to recover the liquid 15.

[0055] In the electrolytic apparatus 1 of this embodiment, it is preferable that the catalyst layer 51 of the cathode section 22 is formed on the second main surface 53 side of the substrate 50. This allows a three-phase interface, which is the reaction field, to be formed on the opposite side of the gas chamber 33, thereby suppressing the flow of the liquid 15 towards the gas chamber 33.

[0056] Next, an electrolytic apparatus 101 of the second embodiment of the present invention will be described. Note that components similar to those in the electrolytic apparatus 1 of the first embodiment are denoted by the same reference numerals and their descriptions are omitted. The same applies hereafter.

[0057] As shown in Figure 3, the electrolytic apparatus 101 of the second embodiment of the present invention comprises an electrolytic cell 102, a first electrolyte supply unit 3, a first recovery unit 5, a material gas supply unit 8, a third recovery unit 10, a power supply unit 11, and a liquid recovery unit 112.

[0058] <Electrolytic cell 102> As shown in Figure 3, the electrolytic cell 102 comprises a cell body 120, an anode 21, a cathode 22, an ion exchange section 23, a first electrolyte introduction section 24, a first discharge section 25, a material gas introduction section 28, a third discharge section 29, and a liquid discharge section 130.

[0059] (Tank body part 120) As shown in Figure 3, the main body of the tank 120 comprises a first tank section 30 and a second tank section 131, and differs from the main body of the tank 20 of the first embodiment in that the second tank section 131 does not have an electrolyte chamber 32. That is, the second tank section 131 is a cathode chamber in which part or all of the cathode section 22 is located, and, like the gas chamber 33, is a storage section for containing material gases.

[0060] (Liquid discharge part 130) As shown in Figure 3, the liquid discharge section 130 is a liquid inlet into which the liquid 15 generated in the cathode section 22 and dripped from the cathode section 22 to the bottom section 42 flows, and is a liquid collection section that collects the incoming liquid 15. The liquid discharge section 130 has an outlet 135 formed on its bottom surface that leads to the liquid recovery section 112, allowing the liquid 15 to be discharged from inside the second tank section 131 to the liquid recovery section 112 through the outlet 135. The liquid discharge section 130 has a bottom surface that slopes downward towards the discharge port 135. That is, the discharge port 135 is located lower than the bottom surface 42, and the liquid 15 that drips from the cathode section 22 onto the bottom surface 42 is guided to the discharge port 135 by gravity.

[0061] <Liquid recovery unit 112> The liquid recovery section 112 is a part that recovers the liquid 15 discharged from the liquid discharge section 130.

[0062] Next, we will describe the gas generation operation that generates oxide gas and carbon compound gas using the electrolytic device 101 of this embodiment.

[0063] In the gas generation operation of this embodiment, first, the first electrolyte 35 is supplied from the first electrolyte supply unit 3 to the first tank unit 30, the first electrolyte 35 is filled to the height of the discharge unit 25 in the first tank unit 30, and then the material gas is supplied from the material gas supply unit 8 to the gas chamber 33 (filling process).

[0064] Then, while supplying the first electrolyte 35 from the first electrolyte supply unit 3 to the first tank unit 30, and recovering the first electrolyte 35 and anode exhaust gas from the first recovery unit 5, material gas is circulated in the gas chamber 33 from the material gas supply unit 8 side toward the third recovery unit 10 side, and a voltage is applied between the anode unit 21 and the cathode unit 22 by the power supply device 11 (voltage application step).

[0065] At this time, the carbon compound gas generated in the cathode section 22 is recovered in the third recovery section 10 as the second cathode exhaust gas along with the unreacted material gas. In addition, the liquid 15 generated in the cathode section 22 flows into the liquid discharge section 130 and is then recovered in the liquid recovery section 112 from the outlet 135.

[0066] In the electrolytic apparatus 101 of the second embodiment, it is preferable to have a liquid recovery unit 112 that recovers the liquid 15 from the liquid discharge unit 130, which is a liquid inlet, in addition to the third recovery unit 10. This makes it easy to separate the liquid 15 from the second cathode exhaust gas.

[0067] In the embodiment described above, a gas diffusion electrode partitioned into an electrolyte chamber 32 and a gas chamber 33 is used as the cathode section 22, and a case is described in which the material gas is reduced on the cathode section 22 to produce a carbon compound gas and a liquid 15, and the liquid 15 is recovered via the gas chamber 33. However, the present invention is not limited to this. A gas diffusion electrode partitioned into an electrolyte chamber and a gas chamber may be used as the anode section 21, and the material gas may be oxidized on the anode section 21 to produce an oxide gas and a liquid, and the liquid may be recovered via the gas chamber. In other words, the liquid recovered by the electrolytic device 1,101 only needs to include what is produced on the anode section 21 or the cathode section 22, and the anode section 21 and the cathode section 22 may be swapped.

[0068] In the embodiment described above, the surface of the top surface 40 constituting the gas chamber 33 on the gas passage 37 side and the surface of the upper wall 44 on the gas passage 37 side formed a perpendicular corner, but the present invention is not limited thereto. The surface of the top surface 40 on the gas passage 37 side and the surface of the upper wall 44 on the gas passage 37 side may form a curved corner gas guide portion 150, as shown in Figure 4(a). In this way, the material gas supplied from the material gas supply unit 8 can be smoothly guided to the cathode unit 22 side (downstream side of the gas passage 37) by the gas guide portion 150.

[0069] In the embodiment described above, the gas passage 37 side surface of the bottom portion 42 constituting the gas chamber 33 and the gas passage 37 side surface of the lower wall portion 45 formed a perpendicular corner, but the present invention is not limited thereto. The gas passage 37 side surface of the bottom portion 42 and the gas passage 37 side surface of the lower wall portion 45 may form a curved corner liquid guide portion 151, as shown in Figure 4(a). In this way, the liquid guide portion 151 can smoothly guide the material gas that has passed through the cathode portion 22 and the liquid 15 generated in the cathode portion 22 to the third discharge portion 29 side (downstream side of the gas passage 37).

[0070] In the embodiment described above, the bottom surface 42 constituting the gas chamber 33 is horizontal, and the liquid 15 is guided to the third discharge section 29 by the flow of the material gas. However, the present invention is not limited to this. The bottom surface 42 constituting the gas chamber 33 may be sloped downward toward the third discharge section 29, as shown in Figure 4(b). This allows the liquid 15 generated in the cathode section 22 to be smoothly guided toward the third discharge section 29 (downstream of the gas flow path 37) by its own weight.

[0071] In the embodiment described above, the first electrolyte 35 was interposed between the anode 21 and the ion exchange 23, but the present invention is not limited thereto, and the anode 21 and the ion exchange 23 may be in direct contact. In this case, it is preferable that the anode 21 be a gas diffusion electrode partitioned into an electrolyte chamber and a gas chamber, similar to the cathode 22.

[0072] In the embodiments described above, the components can be freely substituted or added between each embodiment, as long as they fall within the technical scope of the present invention. [Explanation of Symbols]

[0073] 1,101 Electrolyzer 8. Material Gas Supply Unit (Gas Supply Unit) 10. Third Recovery Section (Gas Recovery Section) 15 liquid 21 Anode section (counter electrode section) 22 Cathode section (gas diffusion electrode section) 28 Material gas introduction section 29 Third discharge section 30 1st tank section (electrolysis chamber) 31 Second tank section 32 Electrolyte chamber (electrolysis chamber) 33 Gas chambers 37 Gas flow path 47 Liquid inlet 50 Base material 51 Catalyst layer 52 First Main Surface 53 Second Main Surface 112 Liquid Recovery Section 130 Liquid discharge part

Claims

1. It comprises a gas diffusion electrode section, a counter electrode section, an electrolysis chamber, a gas chamber, a gas supply section for supplying material gas to the inside of the gas chamber, and a gas recovery section for recovering the gas inside the gas chamber. The gas diffusion electrode portion has a first main surface and a second main surface, the first main surface being exposed to the gas chamber and the second main surface facing the counter electrode portion. The gas diffusion electrode portion can generate a liquid by reducing or oxidizing the material gas by applying a voltage between it and the counter electrode portion. The gas chamber is provided with a liquid inlet at a position lower than the first main surface of the gas diffusion electrode when the first main surface of the gas diffusion electrode is viewed from the front, into which the liquid flows from the gas diffusion electrode. The electrolytic apparatus is configured such that the gas supply unit is located at a position that does not overlap with the gas diffusion electrode unit when the first main surface of the gas diffusion electrode unit is viewed from the front, and is capable of supplying the material gas from a position different from the gas recovery position of the gas recovery unit.

2. The electrolytic apparatus according to claim 1, wherein the gas recovery unit is capable of recovering gas from the gas chamber from a position that does not overlap with the gas diffusion electrode when the first main surface of the gas diffusion electrode is viewed from the front.

3. The gas supply unit is capable of supplying the material gas to a position higher than the center of the gas diffusion electrode unit. The electrolytic apparatus according to claim 2, wherein the gas recovery unit is capable of recovering gas from the gas chamber from a position lower than the supply position of the material gas from the gas supply unit.

4. It has a gas flow path that connects from the gas supply unit through the gas chamber to the gas recovery unit, The liquid inlet is formed in the middle of the gas flow path. The electrolytic apparatus according to any one of claims 1 to 3, wherein the gas recovery unit is capable of recovering the liquid together with the gas from the liquid inlet.

5. The electrolytic apparatus according to any one of claims 1 to 3, further comprising a liquid recovery unit for recovering the liquid from the liquid inlet, separate from the gas recovery unit.

6. The gas diffusion electrode portion comprises a substrate and a catalyst layer. The electrolytic apparatus according to any one of claims 1 to 3, wherein the catalyst layer is formed on the second main surface side of the substrate.

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