JP-2026074589-A - Electrolytic devices and electrolytic systems

Abstract

[Problem] To provide an electrolytic device that can reduce electrolytic energy consumption. [Solution] The electrolytic device 10 is characterized by comprising: an anode electrode 22 containing an anode catalyst that generates protons by electrolytic oxidation of H2 ; a first chamber 24 in which the anode electrode 22 is located and a gas containing H2 is supplied; a second chamber 26 in which an electrolyte containing alkali metal ions is supplied; a cathode electrode 28 containing a cathode catalyst that generates H2 and hydroxide ions by electrolytic reduction of H2O ; a third chamber 30 in which the cathode electrode 28 is located and an aqueous medium is supplied; a first cation exchange membrane 32 located between the first chamber 24 and the second chamber 26; and a second cation exchange membrane 34 located between the second chamber 26 and the third chamber 30. [Selection Diagram] Figure 1

Inventors

• 西村 友作
• 加藤 千和
• 猪飼 正道
• 岡村 和政

Assignees

• 株式会社豊田中央研究所
• トヨタ自動車株式会社

Dates

Publication Date

20260507

Application Date

20241021

Claims (16)

1. An anode electrode containing an anode catalyst that generates protons by electrolytic oxidation of H2 , The anode electrode is placed in a first chamber to which a gas containing H2 is supplied, A second chamber is supplied with an electrolyte containing alkali metal ions, A cathode electrode containing a cathode catalyst, which generates H₂ and hydroxide ions by electrolytic reduction of H₂O , A third chamber is provided, in which the cathode electrode is located and an aqueous medium is supplied. A first cation exchange membrane is disposed between the first chamber and the second chamber, The device comprises a second cation exchange membrane disposed between the second chamber and the third chamber, An electrolytic device characterized in that, when a voltage is applied to the anode electrode and the cathode electrode, the protons generated at the anode electrode are supplied to the second chamber through the first cation exchange membrane, the alkali metal ions in the second chamber are supplied to the third chamber through the second cation exchange membrane, and in the third chamber, an alkali hydroxide aqueous solution is generated by the reaction of the alkali metal ions with the hydroxide ions generated at the cathode electrode.
2. The electrolytic device according to claim 1, characterized in that the anode electrode is in contact with the first cation exchange membrane.
3. The electrolytic device according to claim 1 or 2, characterized in that the cathode electrode is in contact with the second cation exchange membrane.
4. The electrolyte containing alkali metal ions contains carbonate ion species, The electrolytic device according to claim 1 or 2, characterized in that a voltage is applied to the anode electrode and the cathode electrode, causing the proton to react with the carbonate ion species in the second chamber.
5. The electrolytic device according to claim 1 or 2, characterized in that the alkali metal ion comprises at least one of Li + , Rb + , and Cs + .
6. The electrolytic device according to claim 1 or 2, characterized in that the anode catalyst includes a first catalyst that promotes the hydrogen oxidation reaction in an acidic environment.
7. The electrolytic device according to claim 6, characterized in that the anode catalyst includes a second catalyst that promotes the oxygen evolution reaction in an acidic environment.
8. The electrolytic device according to claim 6, characterized in that the first catalyst contains at least one element selected from the group consisting of Pt, Pd, Rh, Re, Au, and Ni.
9. The electrolytic device according to claim 7, characterized in that the second catalyst comprises at least one selected from the group consisting of Ir oxide, Ru oxide, a mixture containing Ir oxide and Ru oxide, and a composite oxide containing Ir and Ru.
10. The electrolytic device according to claim 1 or 2, characterized in that both the first cation exchange membrane and the second cation exchange membrane are perfluorosulfonic acid polymer membranes.
11. The electrolytic device according to claim 1 or 2, characterized in that the cathode catalyst includes a catalyst that promotes the H2 generation reaction.
12. The electrolytic device according to claim 11, characterized in that the cathode catalyst contains at least one element selected from the group consisting of Pt, Pd, Rh, Re, Ni, Co, and Mo.
13. The electrolytic device according to claim 1 or 2, characterized in that the height of the second chamber is 5 mm or less.
14. The electrolytic device according to claim 13, characterized in that the height of the second chamber is 2 mm or less.
15. The electrolytic device according to claim 1 or 2, characterized in that the average linear velocity of the aqueous medium flowing through the third chamber is 15 cm/min or more.
16. The electrolytic device according to claim 1 or 2, A gas-liquid separator for separating the H2- containing discharge liquid from the third chamber into gas and liquid, An electrolysis system characterized by comprising: an H2 supply mechanism that supplies the H2 separated by the gas-liquid separation device to the first chamber.

Description

This invention relates to an electrolytic device and an electrolytic system equipped with said electrolytic device. As technologies that can contribute to carbon neutralization, there is interest in electrolytic devices that utilize electrolysis technology to obtain CO2- reducing valuable products from carbonate ion species (referring to at least one of carbonate ions ( CO3 2- ) and bicarbonate ions ( HCO3- )) or carbon dioxide, and electrodialysis technology that recovers carbon dioxide using an alkaline aqueous solution containing carbonate ion species and separates and concentrates carbon dioxide from the recovered solution containing carbon dioxide. For example, Patent Documents 1-6 and Non-Patent Document 1 disclose an electrodialysis apparatus that separates and concentrates carbon dioxide by applying voltage to the anode and cathode electrodes. Furthermore, Patent Documents 7-12 and Non-Patent Documents 2-3 disclose a technique, not for the purpose of separating and concentrating carbon dioxide, for separating and recovering an aqueous lithium hydroxide solution from the acid treatment solution of the positive electrode active material used in lithium-ion batteries, using electrodialysis technology. Patent Publication No. 5848964Japanese Patent Publication No. 2012-096975Patent Publication No. 5750220Japanese Patent Publication No. 2008-100211International Publication No. 2022/235708Patent Publication No. 5952104Japanese Patent Publication No. 2012-234732Patent Publication No. 7143466Patent Publication No. 6864739Japanese Patent Publication No. 2014-173144Patent Publication No. 7101995International Publication No. 2024/014540 A. Iizuka et al., “Carbon dioxide recovery from carbonate solutions using bipolar membrane electrodialysis”, Separation and Purification Technology, 101, 49(2012)K. H. Chan, M. Malik, and G. Azimi, “Separation of lithium, nickel, manganese, and cobalt from waste lithium-ion batteries using electrodialysis”, Resour. Conserv. Recycl., 178, 106076(2022)J. -M. A. Juve, F. M. S. Christensen, Y. Wang, and Z. Wei, “Electrodialysis for metal removal and recovery: A review”, Chem. Eng. J., 435, 134857(2022) This is a schematic diagram showing an example of an electrolytic system according to this embodiment.This figure shows the measurement results of the applied voltage of the electrolytic device during the electrodialysis test in Examples 1 to 3 and Comparative Examples 1 to 3. Embodiments of the present invention will be described below. This embodiment is an example of implementing the present invention, and the present invention is not limited to this embodiment. Figure 1 is a schematic diagram showing an example of an electrolytic system according to this embodiment. The electrolytic system 1 shown in Figure 1 comprises an electrolytic device 10, a gas-liquid separation device 12, and an H2 supply mechanism 14. The electrolytic device 10 shown in Figure 1 includes an anode electrode 22, a first chamber 24, a second chamber 26, a cathode electrode 28, a third chamber 30, a first cation exchange membrane 32, a second cation exchange membrane 34, and frame members 36a and 36b. The first chamber 24 is provided between the frame member 36a and the first cation exchange membrane 32, and the anode electrode 22 is positioned there. The anode electrode 22 is adjacent to the first cation exchange membrane 32. In the first chamber 24, the space between the anode electrode 22 and the frame member 36a is a flow path 23 through which a gas containing H2 flows. The third chamber 30 is provided between the frame member 36b and the second cation exchange membrane 34, and the cathode electrode 28 is positioned there. The cathode electrode 28 is adjacent to the second cation exchange membrane 34. In the third chamber 30, the space between the cathode electrode 28 and the frame member 36b is a flow path 29 through which an aqueous medium flows. The second chamber 26 is located between the first cation exchange membrane 32 and the second cation exchange membrane 34. Specifically, the first cation exchange membrane 32 is positioned between the first chamber 24 and the second chamber 26, and the second cation exchange membrane 34 is positioned between the second chamber 26 and the third chamber 30. The second chamber 26 is a channel through which an electrolyte containing alkali metal ions and carbonate ion species flows. Here, carbonate ion species refers to at least one of carbonate ions ( CO3²⁻ ) and bicarbonate ions ( HCO3⁻ ). In the electrolytic device 10 shown in Figure 1, the anode electrode 22, cathode electrode 28, cation exchange membrane, etc., are structurally supported by frame materials 36a and 36b. The frame materials 36a and 36b can be made of metal, plastic, glass, etc. The anode electrode 22 is an electrode that includes an anode catalyst and generates protons by the electrolytic oxidation of H₂ . The anode catalyst preferably includes a first catalyst that promotes the hydrogen oxidati