VATIS UPDATE Article

Scientists at Cornell University (Cornell), the United States, have developed an oxygen-assisted aluminum/carbon dioxide (CO2) power cell that uses electrochemical reactions to both sequester the CO2 and produce electricity. In a recent study, Cornell researchers disclosed a novel method for capturing the greenhouse gas and converting it to a useful product – while producing electrical energy. The group’s proposed cell would use aluminum as the anode and mixed streams of CO2 and oxygen as the active ingredients of the cathode.

The electrochemical reactions between the anode and the cathode would sequester the CO2 into carbon-rich compounds while also producing electricity and a valuable oxalate as a byproduct. In most current carbon-capture models, the carbon is captured in fluids or solids, which are then heated or depressurized to release the CO2. The concentrated gas must then be compressed and transported to industries able to reuse it, or sequestered underground. “The fact that we’ve designed a carbon capture technology that also generates electricity is, in and of itself, important,” said Lynden Archer, at Cornell.

Scientists reported that their electrochemical cell generated 13 ampere hours per gram of porous carbon (as the cathode) at a discharge potential of around 1.4 volts. The energy produced by the cell is comparable to that produced by the highest energy-density battery systems. Another key aspect is in the generation of superoxide intermediates, which are formed when the dioxide is reduced at the cathode. The superoxide reacts with the normally inert CO2, forming a carbon-carbon oxalate that is widely used in many industries, including pharmaceutical, fiber and metal smelting.