Dry Reforming of Methane in DBD Plasma over Ni‐Based Catalysts: Influence of Process Conditions and Support on Performance and Durability

Abstract

Greenhouse gases (methane and carbon dioxide) conversion, H2 and CO selectivity, H2/CO ratio and carbon formation in dry reforming reaction (DRM) over Ni supported ZSM‐5, Al2O3 and TiO2 was tested under thermal, plasma and plasma‐thermal conditions. It was observed that the dielectric nature, specific surface area and acid‐base properties of the support influences the performance during DRM reaction. Typical results indicated that the best activity and syngas yield was achieved with 15Ni/Al2O3 under plasma conditions, possibly due to the high dielectric constant and surface area of Al2O3 and nanosize of Ni. In thermal condition, the conversion of CH4 and CO2 over the three catalysts followed the order 15Ni/ZSM‐5 ˃ 15Ni/Al2O3 ˃ 15Ni/TiO2 and the highest conversion of 73% and 68% for CH4 and CO2, respectively was achieved over 15Ni/ZSM‐5 at 500 oC. Plasma assisted thermal conditions provided highest conversion (specifically with 15Ni on ZSM‐5 & Al2O3) due to activation of reactants (radical and ionic species) and their partial conversion in plasma zone before entering to catalytic zone. The plasma assisted thermao‐catalytic conversions of CH4 and CO2 reached the best value of 76% and 71%, respectively on 15Ni/ZSM‐5. Under the same conditions, 68% and 65% conversion of CH4 and CO2 respectively, was achieved with 15Ni/Al2O3 where the selectivity for H2 and CO was 45% and 58%, respectively.