On‐purpose Ethylene Production via CO2‐assisted Ethane Oxidative Dehydrogenation: Selectivity Control of Iron Oxide Catalysts

Abstract

AbstractThe potential of on‐purpose ethylene production, in parallel with CO2 conversion to CO, is of great interest. Iron oxide‐based catalysts supported on mixed oxides zNiO−MgO−ZrO2, z=0–10 wt%, are active for the CO2‐assisted oxidative dehydrogenation of ethane at 873 K and 101.3 kPa. Enhanced control of their selectivity towards C−H bond cleavage and not towards C−C bond cleavage can be achieved by adjusting the Ni/Fe ratio. Fine tuning Ni/Fe molar ratio results in stable catalytic performance, with selectivity towards C2H4 >65 % and C2H6 conversion >20 %. Density functional theory (DFT) calculations show a significant enhancement in activity due to decrease in the oxygen‐vacancy formation energy and the increase in hydrogen adsorption energy at the Ni oxide‐Fe oxide interface. The latter interface is the potential active site responsible for the enhanced performance that was experimentally exemplified for the Fe oxide/zNiO−MgO−ZrO2 catalysts vs Fe oxide/MgO−ZrO2.