Radio-frequency induction heating powered low-temperature catalytic CO2 conversion via bi-reforming of methane

Abstract

Radio-frequency (RF) induction heating of nanoparticles has unfolded novel routes to heterogeneous catalytic chemical reactions. It offers contactless, direct, time- and energy-saving heating with high-achieved catalytic activity. Herein, the tailored chemical synthesis of mono-metallic Cu, binary Cu-Ni, Cu-Co, and ternary Cu-Ni-Co catalysts was evaluated for CO₂ conversion via bi-reforming of methane (combined steam- and dry-reforming processes) under induction heating. All prepared catalysts were activated under RF heating to convert CO₂ and co-reactants i.e., H₂O (steam) and methane into syngas (H₂ and CO) at a relatively low temperature of 400 °C. The Cu-Co sample delivered the highest catalytic performance and stability under all tested conditions. Experimental results elaborated that the concomitant presence of a magnetic element and an electrically conductive component in the catalyst system facilitates highly effective heating occurring via both hysteresis loss and Joule effects mechanisms. On account of Joule heating, the Cu-Co catalyst preserved its excellent stability for at least 50 h over the stream test at a reaction temperature higher than its Curie temperature (T_C). The findings provide significant insights into the catalyst development for RF-assisted chemical reactions that are not needed to be heavily dependent on the use of strong magnetic metals or high input current to obtain desired reactant conversions.