Reduction method and electrolysis system for electrochemical carbon dioxide utilization
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.
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.