Anion exchanger fillings through which flow can occur for electrolyte splitting in co2 electrolysis for better spatial distribution of gassing

Patent metadata

Field	Value
Publication number	US-2021180196-A1
Application number	US-201816771065-A
Country	US
Kind code	A1
Filing date	Nov 19, 2018
Priority date	Dec 21, 2017
Publication date	Jun 17, 2021
Grant date	—

Abstract

An electrolysis cell having a multi-chamber structure, wherein an anion exchanger with a first ion exchanger membrane connects to a cathode chamber, wherein a salt bridge chamber connects to the first ion exchanger membrane, the salt bridge chamber with a fixed anion exchanger. An electrolysis system has such an electrolysis cell and a method for electrolysis of CO2 uses such an electrolysis cell or electrolysis system.

First claim

1 . An electrolysis cell, comprising:
a cathode compartment comprising a cathode; a first ion exchange membrane, which contains an anion exchanger and which is adjacent to the cathode compartment, wherein the cathode comes into contact with the first ion exchange membrane; an anode compartment comprising an anode; and a first separator, which is adjacent to the anode compartment; a salt bridge compartment, wherein the salt bridge compartment is arranged between the first ion exchange membrane and the first separator, wherein the salt bridge compartment comprises a solid anion exchanger, which is at least partially in contact with the first ion exchange membrane.

2 . The electrolysis cell as claimed in claim 1 ,
wherein the solid anion exchanger comprises in the salt bridge compartment cations, which are immobilized in a polymeric backbone.

3 . The electrolysis cell as claimed in claim 1 ,
wherein the solid anion exchanger is present as a bed and/or a porous structure.

4 . The electrolysis cell as claimed in claim 1 ,
wherein the solid salt bridge compartment further comprises uncharged particles, nonionic ion exchangers and/or cation exchangers.

5 . The electrolysis cell as claimed in claim 1 ,
wherein the first separator is a cation exchange membrane, a bipolar membrane or a diaphragm.

6 . The electrolysis cell as claimed in claim 1 ,
wherein the solid anion exchanger is basic, or strongly basic.

7 . The electrolysis cell as claimed in claim 1 ,
wherein the solid anion exchanger is hydrophilic.

8 . The electrolysis cell as claimed in claim 1 ,
wherein the salt bridge compartment further comprises a solid cation exchanger, which is at least partially in contact with the first separator.

9 . An electrolysis system, comprising:
an electrolysis cell as claimed in claim 1 .

10 . The electrolysis system as claimed in claim 9 , further comprising:
a return device that is connected to an outlet of the salt bridge compartment and an inlet of the cathode compartment, which is configured to recycle a reactant of the cathode reaction, which can be formed in the salt bridge compartment, back into the cathode compartment.

11 . A method for the electrolysis of CO 2 with an electrolysis cell as claimed in claim 1 , the method comprising:
reducing CO 2 at the cathode, wherein hydrogencarbonate and/or carbonate generated at the cathode by the first ion exchange membrane migrates to an electrolyte in the salt bridge compartment, wherein the hydrogencarbonate and/or carbonate is also transported through the solid anion exchanger in the salt bridge compartment away from the first ion exchange membrane.

12 . The method as claimed in claim 11 ,
wherein the salt bridge compartment comprises an aqueous electrolyte.

13 . The method as claimed in claim 11 ,
wherein the electrolyte of the salt bridge compartment comprises an acid, or a water-soluble acid, or a water-miscible acid.

14 . The method as claimed in claim 11 ,
wherein the electrolyte of the salt bridge compartment essentially comprises no mobile cations other than H + and/or hydrated variants thereof.

15 . A method for the electrolysis of CO 2 and/or CO, the method comprising:
performing electrolysis using the electrolysis cell as claimed in claim 1 .

16 . The electrolysis cell as claimed in claim 2 ,
wherein the cations exchange hydrogencarbonate and/or carbonate ions.

17 . The electrolysis cell as claimed in claim 4 ,
wherein the uncharged particles, nonionic ion exchangers and/or cation exchangers are contained in an area adjacent to the first ion exchange membrane in an amount of up to 20 vol. %, based on the total amount of the solid anion exchanger and the uncharged particles, nonionic ion exchangers and/or cation exchangers.

18 . The electrolysis cell as claimed in claim 4 ,
wherein the uncharged particles and/or nonionic ion exchangers are contained in an area adjacent to the first ion exchange membrane in an amount of up to 20 vol. %, based on the total amount of the solid anion exchanger and the uncharged particles, nonionic ion exchangers and/or cation exchangers.

Assignees

• Siemens Ag

Inventors

• Schmid Bernhard
• Schmid Günter
• Reller Christian
• Taroata Dan

Classifications

• C25B1/00

  Electrolytic production of inorganic compounds or non-metals · CPC title

• C25B13/02

  characterised by shape or form · CPC title

• C25B9/23 Primary

  comprising ion-exchange membranes in or on which electrode material is embedded · CPC title

• C25B3/26

  of carbon dioxide · CPC title

• C25B1/23

  Carbon monoxide or syngas · CPC title