Reduction method and electrolysis system for electrochemical carbon dioxide utilization

Patent metadata

Field	Value
Publication number	US-10760170-B2
Application number	US-201615739738-A
Country	US
Kind code	B2
Filing date	May 31, 2016
Priority date	Jul 3, 2015
Publication date	Sep 1, 2020
Grant date	Sep 1, 2020

Abstract

The present disclosure relates to electrolysis. For example, an electrolysis system for carbon dioxide utilization may include: an electrolysis cell having an anode and a cathode, where carbon dioxide reduces at the cathode to at least one hydrocarbon compound or to carbon monoxide; first and second electrolyte reservoirs; a first product gas line from the first electrolyte reservoir; a second product gas line from the second electrolyte reservoir; a first connecting line supplying electrolyte from the first electrolyte reservoir to the anode; a second connecting line taking electrolyte from the anode to the second electrolyte reservoir; a third connecting line supplying electrolyte from the second electrolyte reservoir to the cathode; a fourth connecting line taking electrolyte from the cathode off to the first electrolyte reservoir; and a pressure-equalizing connection directly connecting the first and second electrolyte reservoirs.

First claim

What is claimed is:

1. An electrolysis system for carbon dioxide utilization, the system comprising:
an electrolysis cell having an anode in an anode chamber and a cathode in a cathode chamber;
the cathode chamber exposing carbon dioxide to contact with the cathode to enable catalysis of a reduction reaction of carbon dioxide to at least one hydrocarbon compound or to carbon monoxide;
first and second electrolyte reservoirs;
a first product gas line leading from the first electrolyte reservoir;
a second product gas line leading from the second electrolyte reservoir;
a first connecting line supplying electrolyte from the first electrolyte reservoir to the anode chamber;
a second connecting line taking electrolyte from the anode chamber off to the second electrolyte reservoir;
a third connecting line supplying electrolyte from the second electrolyte reservoir to the cathode chamber;
a fourth connecting line taking electrolyte from the cathode chamber off to the first electrolyte reservoir; and
a pressure-equalizing connection directly connecting the first and second electrolyte reservoirs.

2. The electrolysis system as claimed in claim 1 , further comprising a pump in the pressure-equalizing connection.

3. The electrolysis system as claimed in claim 2 , further comprising a level sensor for each reservoir.

4. The electrolysis system as claimed in claim 1 , wherein the two electrolyte reservoirs comprise a single container having a dividing wall for subdivision into the two electrolyte reservoirs;
wherein the dividing wall comprises an opening providing the pressure-equalizing connection.

5. The electrolysis system as claimed in claim 1 , further comprising means for the introduction of inert gas into the reservoirs.

6. The electrolysis system as claimed in claim 1 , further comprising a supply line for supplying the carbon dioxide.

7. The electrolysis system as claimed in claim 6 , wherein the supply line for supplying the carbon dioxide includes an overpressure valve.

8. The electrolysis system as claimed in claim 6 , wherein the supply line and the first product gas line are joined.

9. The electrolysis system as claimed in claim 1 , wherein the first product gas joins the second product gas line at an overpressure valve.

10. A reduction method for carbon dioxide utilization with an electrolysis system, the method comprising:
passing carbon dioxide through a cathode chamber of an electrolysis cell to bring the carbon dioxide into contact with a cathode;
reducing the carbon dioxide to a hydrocarbon compound or to carbon monoxide;
passing a first product gas through a first product gas line out of a first electrolyte reservoir;
passing a second product gas through a second product gas line out of a second electrolyte reservoir;
passing electrolyte from the first electrolyte reservoir to an anode chamber of the electrolysis cell;
passing electrolyte from the anode chamber to the second electrolyte reservoir;
passing electrolyte from the second electrolyte reservoir to the cathode chamber;
passing electrolyte from the cathode chamber to the first electrolyte reservoir; and
maintaining a shared liquid level in the electrolyte reservoirs by means of a pressure-equalizing connection between the first and second electrolyte reservoirs.

11. The reduction method as claimed in claim 10 , further comprising pumping liquid through the pressure-equalizing connection.

12. The reduction method as claimed in claim 11 , further comprising activating a pump in the pressure-equalizing connection based on a reading from a level sensor for each reservoir.

13. The reduction method as claimed in claim 10 , wherein the two electrolyte reservoirs comprise a single container having a dividing wall for subdivision into the two electrolyte reservoirs; and
wherein the dividing wall comprises an opening providing the pressure-equalizing connection.

14. The reduction method as claimed in claim 10 , further comprising introducing an inert gas into the reservoirs.

15. The reduction method as claimed in claim 10 , further comprising supplying the carbon dioxide through a supply line.

16. The reduction method as claimed in claim 15 , wherein the supply line for supplying the carbon dioxide includes an overpressure valve.

17. The reduction method as claimed in claim 15 , wherein the supply line and the first product gas line are joined.

18. The reduction method as claimed in claim 10 , wherein the product gas lines join at an overpressure valve.

Assignees

• Siemens Ag

Inventors

• Fleischer Maximilian
• Jeanty Philippe
• Krause Ralf
• Magori Erhard
• Romero Cuéllar Nayra Sofia
• Schmid Bernhard
• Schmid Günter
• Wiesner-Fleischer Kerstin

Classifications

• C25B3/25

  Reduction · CPC title

• C25B9/17

  Cells comprising dimensionally-stable non-movable electrodes; Assemblies of constructional parts thereof · CPC title

• C25B15/08 Primary

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

• C25B1/00

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

• C25B3/04

  Chemistry & Metallurgy · mapped topic