Preparation Of Nickel Catalyst For CO₂ Reforming Of Methane By Dielectric-barrier Discharge Plasma

CO2 reforming of methane provides a practical method for the conversion of greenhouse gases (CH4 and CO2) to produce syngas with a low H2/CO ratio, which is suitable for Fischer-Tropsch synthesis of long-chain hydrocarbons. Moreover, it is a potential way for the utilization of clean energy feedstocks, such as biogas and natural gas. Therefore, CO2 reforming of methane has become one of the most extensively studied reactions. Among the catalysts investigated for CO2 reforming of methane, nickel-based catalyst has aroused more attention because of high catalytic activity and low cost, but the major problem is its deactivation. Recently, non-equilibrium plasma, a new molecule activation technology, has been used in catalyst preparation.In this work,5% Ni/SiO2 catalysts for CO2 reforming of methane were prepared by several procedures using plasma-activated method and their catalytic performance in CO2 reforming of methane were compared. The results indicated that the plasma-activated catalysts, especially the catalyst activated directly by plasma, exhibited relatively higher activity and very lower water yield than the conventional catalyst. XRD analyses confirmed that the plasma-activated catalyst had smaller particle size, an enhanced dispersion.A novel plasma-treated Ni/MgO catalyst was prepared by treating coprecipitated NiCO3-MgCO3 with dielectric-barrier discharge plasma. The results by XRD, TEM and N2 adsorption analyses showed that the plasma-prepared Ni/MgO catalyst possessed smaller particle size, enhanced nickel dispersion, and higher specific surface area than a conventionally reduced Ni/MgO catalyst. The plasma-prepared Ni/MgO catalyst also exhibited better catalytic activity for CO2 reforming of methane than the catalyst prepared by conventional method.