Activation of methane and carbon dioxide in a dielectric-barrier discharge-plasma reactor to produce hydrocarbons—Influence of La2O3/γ-Al2O3 catalyst

The activation of methane and carbon dioxide to produce hydrocarbons has been investigated in a dielectric barrier discharge (DBD) reactor. A high CH4/CO2 ratio is more selective for the production of C2 hydrocarbons, but the carbon balance is always far from 100% due to carbon deposition and formation of heavy molecules. An increase of the reaction temperature until 600 °C is more favorable for ethylene formation. The presence of glass or alumina balls in the plasma improves the stability of the plasma discharge leading to an increase of the CO2 and CH4 conversion. The use of the catalyst La2O3/γ-Al2O3 in the plasma zone, at 400 °C, modifies significantly the activation of carbon dioxide while it does not affect the activation of methane. This result can be attributed to the formation of surface oxycarbonate species responsible for the higher carbon monoxide selectivity.