Plasma catalytic hybrid reforming of methane

Non-thermal plasma induced steam reforming of methane has been investigated applying a dielectric barrier discharge (DBD) reactor for pure plasma processes and a dielectric packed bed (DPB) reactor for plasma catalytic hybrid processes. Neither the H2O conversion nor the yield and energy efficiency of H-2-formation of the DBD reactor showed to be sufficient for practical application. This could be explained by numerical simulation showing low H2O dissociation rates and high losses due to vibrational excitation of H2O and radical recombination. In contrast by plasma catalytic hybrid reforming using nickel as a catalyst good H2O conversion and high selectivity towards H-2 were obtained. Compared to pure DBD treatment at a temperature of 400 degreesC the energy requirements for H-2-generation were reduced for a factor 10 down to about 700 kJ/mol. The other reaction products at that temperature were CO2 and small amounts of CO. Between 400 degreesC and 600 degreesC the CO2-yield increased less than the H-2-yield and increasing amounts of CO were formed, whereas at lower temperatures substantial amounts of C2H6 were detected.