Method and system for electrochemical reduction of carbon dioxide employing a gas diffusion electrode
The present disclosure is a method and system for the reduction of carbon dioxide. The method may include receiving hydrogen gas at an anolyte region of an electrochemical cell including an anode, the anode including a gas diffusion electrode, receiving an anolyte feed at an anolyte region of the electrochemical cell, and receiving a catholyte feed including carbon dioxide and an alkali metal bicarbonate at a catholyte region of the electrochemical cell including a cathode. The method may include applying an electrical potential between the anode and cathode sufficient to reduce the carbon dioxide to at least one reduction product.
1. A method for reducing carbon dioxide, comprising:
receiving an anolyte feed at an anolyte region of an electrochemical cell, the electrochemical cell including an anode, wherein the anolyte includes water and a hydrogen halide;
receiving a feed of carbon dioxide gas at a catholyte region of the electrochemical cell including a cathode, the cathode including a gas diffusion electrode;
wherein the cathode gas diffusion electrode comprises a catalyst for the reduction of carbon dioxide, deposited on a support, in a three-dimensional structure, the cathode gas diffusion electrode including a hydrophobic binder and/or filler between the structure and a membrane;
receiving a catholyte feed including carbon dioxide and an alkali metal bicarbonate at the catholyte region of the electrochemical cell; and
applying an electrical potential between the anode and the cathode of the electrochemical cell sufficient to reduce the carbon dioxide to an alkali metal formate and co-produce a halogen.
2. The method of claim 1 , wherein the hydrogen halide includes at least one of hydrogen bromide or hydrogen chloride.
3. The method of claim 1 , further comprising:
converting the alkali metal formate to an alkali metal oxalate via a thermal reaction;
receiving the alkali metal oxalate at an electrochemical acidification electrolyzer; and
converting the alkali metal oxalate to oxalic acid and co-producing alkali metal hydroxide, hydrogen, and a halogen at the electrochemical acidification electrolyzer.