Electrochemical reaction device, method of reducing carbon dioxide, and method of producing carbon compounds

Patent metadata

Field	Value
Publication number	US-2022282384-A1
Application number	US-202217681866-A
Country	US
Kind code	A1
Filing date	Feb 28, 2022
Priority date	Mar 4, 2021
Publication date	Sep 8, 2022
Grant date	—

Abstract

An object is to provide an electrochemical reaction device in which unreacted carbon dioxide gas is less likely to be mixed in and the purity of carbon compounds generated by reduction can be improved, a method of reducing carbon dioxide using the same, and a method of producing carbon compounds. In an electrochemical reaction device 100 that electrochemically reduces carbon dioxide, a first reaction unit 110, and a second reaction unit 120 provided on a downstream side of the first reaction unit are provided, the first reaction unit 110 includes a first liquid flow path 113 in which an inlet and an outlet between the first cathode 111 and the first anode 112 are closed in an openable and closable manner, and a first gas flow path 114 in which an inlet and an outlet on a side of the first cathode 111 opposite to the first anode 112 are closed in an openable and closable manner, and the second liquid flow path 123 for supplying an electrolyte from the first liquid flow path 113, in which an inlet and an outlet are closed in an openable and closable manner, is provided between a second cathode 121 and a second anode 122 of the second reaction unit 120.

First claim

What is claimed is:

1 . An electrochemical reaction device that electrochemically reduces carbon dioxide, comprising:
a first reaction unit; and a second reaction unit provided on a downstream side of the first reaction unit, wherein the first reaction unit includes a first cathode, a first anode, a first liquid flow path provided between the first cathode and the first anode for supplying an electrolyte composed of a strong alkaline aqueous solution, a first gas flow path provided on a side of the first cathode opposite to the first anode for supplying carbon dioxide gas, a first liquid flow path closing means for closing an inlet and an outlet of the first liquid flow path in an openable and closable manner, and a first gas flow path closing means for closing an inlet and an outlet of the first gas flow path in an openable and closable manner, and the second reaction unit includes a second cathode, a second anode, a second liquid flow path provided between the second cathode and the second anode for supplying the electrolyte from the first liquid flow path, a second gas flow path provided on a side of the second cathode opposite to the second anode, a second liquid flow path closing means for closing an inlet and an outlet of the second liquid flow path in an openable and closable manner, and a second gas flow path closing means for closing an inlet and an outlet of the second gas flow path in an openable and closable manner.

2 . A method of electrochemically reducing carbon dioxide, the method comprising:
a step of electrochemically reducing carbon dioxide gas and dissolving unreacted carbon dioxide gas in an electrolyte in a state where the electrolyte composed of a strong alkaline aqueous solution is accommodated in a first liquid flow path in which an inlet and an outlet between a first cathode and a first anode are closed, and the carbon dioxide gas is accommodated in a first gas flow path in which an inlet and an outlet on a side of the first cathode opposite to the first anode is closed; and a step of electrochemically reducing dissolved carbon dioxide in the electrolyte in a second liquid flow path by moving the electrolyte in which carbon dioxide dissolves from the first liquid flow path to the second liquid flow path between a second cathode and a second anode.

3 . The method of reducing carbon dioxide according to claim 2 , wherein
an average value of voltages applied between the first cathode and the first anode during the reduction of the carbon dioxide gas is set to be lower than an average value of voltages applied between the second cathode and the second anode during the reduction of the dissolved carbon dioxide.

4 . A method of producing carbon compounds by electrochemically reducing carbon dioxide by using the method of reducing carbon dioxide according to claim 2 .

Assignees

• Honda Motor Co Ltd

Inventors

• Shimada Yuta
• Oikawa Hiroshi

Classifications

• C25B9/70 Primary

  Assemblies comprising two or more cells · CPC title

• C25B15/08

  Supplying or removing reactants or electrolytes; Regeneration of electrolytes · CPC title

• C25B3/03

  Acyclic or carbocyclic hydrocarbons · CPC title

• C25B1/04

  by electrolysis of water · CPC title

• C25B1/50

  Processes · CPC title