Patent ID: 8227127

Claim:
An electrochemical apparatus to sequester carbon dioxide from gas streams and generate hydrogen comprising: a) an electrolysis chamber, electrically connected to an electrical energy source and comprising at least one cathode, at least one anode, and a substantially chloride-free aqueous electrolyte solution, the electrolysis chamber further comprising a first region adapted to concentrate hydroxide ions produced at the cathode and a second region adapted to concentrate hydronium ions produced at the anode when direct current is applied to the electrolysis chamber; b) a gas contact assembly operably connected to the first region of the electrolysis chamber and adapted to receive hydroxide ions in solution from the electrolysis chamber and to contain a gas stream containing carbon dioxide; c) gas supply equipment adapted to provide the gas stream containing carbon dioxide to the gas contact assembly to contact hydroxide ions in solution with the carbon dioxide and react the hydroxide ions with the carbon dioxide to form bicarbonate or carbonate ions in solution; and d) a separation chamber operably connected to the gas contact assembly and adapted to separate the bicarbonate or carbonate ions from the solution in the gas contact assembly; wherein, the electrolysis chamber is configured to produce less than about 100 milligrams of chlorine per liter of the electrolyte solution.