Carbon dioxide reforming of methane to synthesis gas by an atmospheric pressure plasma jet

An experimental investigation on CO2 reforming of CH4 to synthesis gas was performed using a novel atmospheric pressure plasma jet, which is initiated by an alternating current of 50 Hz and a high ratio transformer. The plasma jet proved to be a stable and uniform atmospheric pressure discharge that held the advantages of both thermal and nonthermal plasma. The effects of discharge distance, CH4:CO2 mol ratio in the feed, feed flow rate, and discharge power on the reforming reaction were investigated. The results showed that the products of the reforming reaction are simple, including H2, CO, a small amount of H2O, and carbon powder. The optimal discharge distance between two electrodes is 9 mm, and the optimal CH4:CO2 mol ratio is 4:6. When the flow rate is 1000 mL/min and the discharge power is 88.4 W, the conversions of CH4 and CO2 are 94.99% and 87.23%, respectively, which are higher than those via other plasmas. The conversions of CH4 and CO2 increase with increasing the discharge power and decrease with increasing the flow rate. Current process is more advantageous in treatment capacity and conversion ability for carbon dioxide reforming of methane than other plasma systems.