Synergistic promotions of K doping on CO2 capture and in situ conversion

Abstract

AbstractThe integrated CO2 capture and conversion (iCCC) technology has been recognized as a promising strategy for upcycling the emitted CO2 into artificial carbon sequestration but still demands highly efficient dual functional materials (DFMs). We develop an efficient iCCC process of the integrated lithium‐looping (LiL) and reverse water gas shift reaction through deeply understanding K doping in the novel Kx‐Li4SiO4@Niy DFMs. The appropriate K doping enables the fast diffusion of CO2 and H2 into the bulk DFMs through forming LiKCO3 surface eutectic layer as well as strongly interacts with catalyst Ni to generate new medium basic sites for synergistic promotions of CO2 capture and in situ conversion. More importantly, after the pelletization, the LP‐K0.2‐Li4SiO4@Ni10 DFM (20–40 mesh) avoids the agglomeration and achieves an excellent and stable iCCC cycle performance, with CO2 capture capacity of 3.8 mmol/g, CO2 conversion efficiency of 90%, and CO selectivity close to 100% at 550°C in one fixed‐bed column.