Partial Oxidation of CH₄ in Plasma: The Effects of Oxidant and Catalyst Addition

The partial oxidation of methane in cold atmospheric plasma represents an innovative and promising approach to energy conversion and sustainable chemical processes for obtaining various chemicals and fuels. In present work, dielectric barrier discharge plasma is applied to the partial oxidation of CH₄ combined with Cu-containing catalysts. The catalysts with different porous and acidic properties were obtained, characterized by physico-chemical methods and used in plasma-catalytic reaction. The influence of the oxidizing agent (oxygen vs. air) on the products' selectivity and yield was studied. It was found that using air as an oxidizer was beneficial in terms of CH₄ conversion and gaseous products yield, as N₂ aided in denser microdischarge formation. Using pure O₂ for methane partial oxidation resulted in enhanced oxygenate (mainly CH₃OH) generation. Furthermore, the Cu-containing catalysts enhanced methanol yield compared to the plasma-only process, as well as the energy efficiency of the process.