Reaction ignition during the oxidative coupling of methane over Mn–Na2WO4/SiO2

Abstract

The present study investigates the oxidative coupling of methane (OCM) as a viable solution for CH₄ upgrading with the benchmark Mn–Na₂WO₄/SiO₂ catalyst. The effects of space velocity on catalytic performance and ignition responses were evaluated. Experimental catalytic tests revealed a complex relationship between space velocity and C2+ product yields and a self-igniting behavior when the reaction temperature reached about 700 °C. The results indicated that the temperature difference (∆T) between the catalyst bed and the flowing gas increased with the feed flow rate and decreased with dilution of the catalyst bed (increasing with catalyst loading), which can allow the reaction ignition at lower temperatures. The present study sheds light on the interplay between reaction conditions and the ignition behavior, providing valuable insights for optimization of OCM processes and catalyst development.