The effect of hydrogen peroxide concentration on the partial oxidation of methane to methanol in an atmospheric dielectric barrier discharge

摘要

It was proved that atmospheric non-equilibrium plasma can be deemed as “reaction carrier”, and is an effective method of partial oxidation of methane to methanol and other higher hydrocarbons. In this paper, hydrogen peroxide vapor is selected as oxygen-containing oxidizer and used to activate and convert methane into methanol in an atmospheric dielectric barrier discharge. A detailed axisymmetric 2D fluid model in CH4/H2O/H2O2 gas mixture is developed, with an emphasis on gas-phase plasma chemistry for partial oxidation of methane and methanol formation. Especially, the effect of hydrogen peroxide concentration on the conversion of methane to methanol is studied. The spatial and temporal distributions of various plasma species are shown as a function of hydrogen peroxide concentration. In addition, the main plasma species and reaction pathways governing the production and loss of CH3OH and OH are determined. It is shown that the increasing hydrogen peroxide concentration results in increase of OH and CH3OH production. Hydroxyl appears to play a significant role during the process of methanol synthesis, which is primarily produced by electron-impact dissociation of H2O2 and H2O molecules.