Plasma-assisted catalytic oxidation of methane: On the influence of plasma energy deposition and feed composition

The total oxidation of methane was carried out within a dielectric barrier discharge (DBD) reactor. The effect of energy deposition was studied, with energy deposition ranging from 36 to 100 J L−1. In the current study, we also investigated the combined process of a dielectric barrier discharge and γ-alumina catalyst in the total oxidation of methane. In order to separate the catalytic effects from the plasma activation, the work included both purely catalytic and plasma activation processes. It was found that the catalytic activity depended on the energy deposition and the temperature. The plasma process leads to methane conversion in the temperature range of 300–500 °C, whereas, methane conversion was only active above 425 °C when only a catalyst was present. Moreover, the addition of NOx and CO2 in the feed was also studied. This addition does not affect the methane conversion in the absence or in the presence of catalyst. Finally, the presence of γ-alumina leads to CO + CO2 as products of the total oxidation of methane, whereas for the plasma-induced process, CO is the major product of the reaction.