Carbon dioxide reduction in a tubular solid oxide electrolysis cell for a carbon recycling energy system

A new energy transformation system based on carbon recycling is proposed called the active carbon recycling energy system (ACRES). A high-temperature gas reactor was used as the main energy source for ACRES. An experimental study based on the ACRES concept of carbon monoxide (CO) regeneration via high-temperature reduction of carbon dioxide (CO2) was carried out using a tubular solid oxide electrolysis cell employing Ni-LSM cermet vertical bar YSZ vertical bar YSZ-LSM as the cathode vertical bar electrolyte vertical bar anode. The current density increased with increasing CO2 concentration at the cathode, which was attributed to a decrease in cathode activation and concentration overpotential. Current density, as well as the CO and oxygen (O-2) production rates, increased with increasing operating temperature. The highest CO and O-2 production rates of 1.24 and 0.64 mu mol/min cm(2), respectively, were measured at 900 degrees C. Based on the electrolytic characteristics of the cell, the scale of a combined ACRES CO2 electrolysis/iron production facility was estimated. (C) 2013 Elsevier B.V. All rights reserved.