Non-Thermal Plasma-Assisted Catalytic Dry Reforming of Methane and Carbon Dioxide Over G-C₃N₄-Based Catalyst

In the present study, pure plasma and plasma-assisted catalytic activation of reforming of methane and carbon dioxide into syngas production were performed in a coaxial dielectric barrier discharge (DBD) plasma reactor at low temperature. For pure plasma, higher input power was favorable for the conversions of CH₄ and CO₂ but led to lower selectivities of syngas, while selectivities of syngas increased under lower flow rate of feed gases. A high CH₄/CO₂ ratio was more selective for C₂ hydrocarbon formation. Novel g-C₃N₄-based catalysts were prepared and filled in the discharge gap at low temperature. The cooperation effect of DBD plasma with g-C₃N₄ catalyst was achieved that contributed more to the activation of carbon dioxide than that of methane as well as the yield of CO for its low reduction potential. TiO₂/g-C₃N₄ with heterogeneous structure as packing the catalyst bulks into the discharge zone was capable of further improving the reforming of methane and carbon dioxide. TiO₂ mass ratio exhibited significant effect on dry reforming reactions and only TiO₂/g-C₃N₄ with 1% TiO₂ mass ratio presented enhanced hybrid effect than that of g-C₃N₄ catalyst.