AUTHOR=Charalambous Christina , Xu Shanshan , Ding Shengzhe , Chansai Sarayute , Asuquo Edidiong , Torres Lopez Antonio , Parlett Christopher M. A. , Gilmour Jamie D. , Garforth Arthur , Hardacre Christopher TITLE=Non-thermal plasma activated CO2 hydrogenation over K- and La- promoted layered-double hydroxide supported Ni catalysts JOURNAL=Frontiers in Chemical Engineering VOLUME=4 YEAR=2022 URL=https://www.frontiersin.org/journals/chemical-engineering/articles/10.3389/fceng.2022.1027167 DOI=10.3389/fceng.2022.1027167 ISSN=2673-2718 ABSTRACT=

The catalytic conversion of CO2 to CH4 and CO over nickel particles supported on layered-double hydroxide (MgAl) with different metal promoters was investigated under non-thermal plasma (NTP) conditions. It has been shown that lanthanum-promoted Ni catalysts significantly enhanced the CO2 conversion in comparison to the 10Ni/MgAl catalyst (33.4% vs. 89.3%). In comparison, for the potassium-promoted catalysts, CO2 conversion is similar to that of 10Ni/MgAl but the CO selectivity increased significantly (35.7% vs. 62.0%). The introduction of La and K to Ni catalysts increased the Ni dispersion and improved the reducibility of Ni species, thus affecting CO2 conversion and product selectivity. In situ DRIFTS showed similar reaction pathways for La- and K- promoted catalysts with Ni catalysts. However, the La and K promoters significantly improved the formation of formate species on the Ni surface, facilitating CO2 conversion to useful products.