O2–CO2 Mixed Gas Production Using a Zr-Doped Cu-Based Oxygen Carrier

Abstract

Oxyfuel combustion using O2–CO2 mixed gas as the oxidant is a promising technology for effectively capturing high concentration CO2. Chemical looping air separation (CLAS) is a novel approach with a low energy footprint for O2–CO2 mixed gas production. In this work, a series of Zr-doped Cu-based oxygen carriers were prepared by the sol–gel combustion method and used to produce the O2–CO2 gas mixture. The effects of doping Zr on phase structure, surface topography, O2 absorption/desorption, and cyclic reaction of Cu-based oxygen carriers were studied by experiments. The influencing mechanism of Zr doping on O2 release of Cu-based oxygen carrier was investigated using density functional theory (DFT) calculations. The results indicate that the addition of Zr enlarges the specific surface area and refines the grains. The Zr-doped Cu-based oxygen carriers have high desorption reaction rates. The oxygen release capacity increases with the increasing Zr doping amount. The cyclic operation indicates that the Zr-d...