Dry reforming of methane in a nanosecond repetitively pulsed discharge: chemical kinetics modeling

Abstract

Nanosecond pulsed discharge plasma shows a high degree of non-equilibrium, and exhibits relatively high conversions in the dry reforming of methane. To further improve the application, a good insight of the underlying mechanisms is desired. We developed a chemical kinetics model to explore the underlying plasma chemistry in nanosecond pulsed discharge. We compared the calculated conversions and product selectivities with experimental results, and found reasonable agreement in a wide range of specific energy input. Hence, the chemical kinetics model is able to provide insight in the underlying plasma chemistry. The modeling results predict that the most important dissociation reaction of CO2 and CH4 is electron impact dissociation. C2H2 is the most abundant hydrocarbon product, and it is mainly formed upon reaction of two CH2 radicals. Furthermore, the vibrational excitation levels of CO2 contribute for 85% to the total dissociation of CO2.