Carbon dioxide electrolytic device and method of controlling carbon dioxide electrolytic device

A carbon dioxide electrolytic device, comprising:

• a carbon dioxide electrolysis cell having
• a cathode flow path through which carbon dioxide flows,
• an anode flow path through which an electrolytic solution containing water flows,
• a cathode on or in the cathode flow path, the cathode being configured to reduce the carbon dioxide to produce a carbon compound,
• an anode on or in the anode flow path, the anode being configured to oxidize the water to produce oxygen, and
• a first diaphragm between the anode flow path and the cathode flow path;
• a first current regulator configured to supply a first current to the carbon dioxide electrolysis cell;
• a first gas/liquid separator configured to separate a first fluid to be discharged from the anode flow path into a first liquid and a first gas;
• an electrodialysis cell having
• a first room, a first electrode in the first room,
• a second room, a second electrode in the second room,
• a third room between the first room and the second room, the third room being configured to store the first liquid to be supplied from the first gas/liquid separator,
• a fourth room between the third room and the second room,
• a second diaphragm between the first room and the third room,
• a third diaphragm between the second room and the fourth room, and
• a fourth diaphragm between the third room and the fourth room;
• a second current regulator configured to supply a second current to the electrodialysis cell;
• at least one detector selected from the group consisting of a first detector and a second detector, the first detector being configured to detect a flow rate of the first gas or a concentration of carbon dioxide contained in the first gas, and the second detector being configured to detect a pH of the first fluid or a concentration of at least one ion contained in the first fluid;
• and
• a first controller configured to control the second current regulator to regulate a value of the second current, in accordance with at least one detection signal from the at least one detector.