Investigating the effects of helium, argon and hydrogen co-feeding on the non-oxidative coupling of methane in a dielectric barrier discharge reactor
Pierre-André Maitre, James W. Long, M. S. Bieniek, Marcus N. Bannerman, Panagiotis N. Kechagiopoulos
Abstract
The impact of helium, argon, and hydrogen co-feeding on methane non-oxidative coupling in dielectric barrier discharges is investigated in terms of reaction pathways and energy efficiency. One-dimensional fluid simulations are used to investigate short time-scales. Zero-dimensional global modelling, using inputs from the one-dimensional simulations, is utilised to study time-scales equivalent to those of experimental reactors. A previously developed detailed kinetic scheme for non-thermal methane plasma that accounts for the reactivity and relaxation of electronically and vibrationally excited species is extended to describe the interactions of noble gases with the species within the methane plasma. A wide range of compositions and applied voltages are studied to determine the conditions that improve the energy efficiency of methane conversion and the selectivity to value-added products. Penning dissociation has a significant impact in the case of mixtures with high content of argon, while hydrogen co-feeding increases selectivity towards ethane and ethylene versus acetylene.