About the nickel amount deposited on silica-alumina for ethylene production through oxidative dehydrogenation of ethane

Abstract

This work explores the deposition of different nickel amounts (20 – 80 wt% Ni) on a silica-alumina support to prepare catalysts for ethylene production through the oxidative dehydrogenation of ethane (ODHE). The nickel species features and their distribution on the support had an important effect on their reducibility and interactions, and consequently on their catalytic performance. At low nickel loadings (20 – 40 wt%) highly ethylene-selective formulations were obtained driven by small and well-distributed NiO particles with moderate-to-hard reducibility and high interaction with the support. Contrarily, higher nickel amounts generated bigger NiO aggregates and more reducible Ni2+ species. Therefore, the NiO-support interactions got weakened and ethylene selectivity suffered a slight drop for nickel contents of 50 and 60 wt%, and an additional decrease for 80 wt%. Nevertheless, all catalysts maintained a remarkable selectivity to ethylene even with an increased ethane conversion, demonstrating the valuable capacity of this novel support.