Direct conversion of methane and carbon dioxide to higher hydrocarbons using catalytic dielectric-barrier discharges with zeolites

Direct higher hydrocarbon formation from the greenhouse gases methane and carbon dioxide using a dielectric-barrier discharge (DBD) with zeolite catalysts is presented. This catalytic DBD can be operated at ambient conditions and leads to direct hydrocarbon formation. The products include alkanes, alkenes, oxygenates, and syngas (CO + H-2). The product distribution depends on the pressure, the input power, the flow rate, the CH4/CO2 feed ratio, and the catalyst used. It is not sensitive to gas temperature in the range from room temperature to 150 degrees C. From the experiments it can be concluded that a cogeneration of syngas and higher hydrocarbons can be achieved using the catalytic DBD. The optimum CH4/CO2 ratio in the feed for such cogeneration is in the range 2/1 to 3/1. The energy efficiency of CO2 and CH4 conversion increases substantially at higher discharge powers.