Nickel Supported Modified Zirconia Catalysts for CO<sub>2</sub> Methanation in DBD Plasma Catalytic Hybrid Process

The methanation reaction has recently received considerable attention as a perspective CO2 utilization technology leading to the formation of renewable natural gas methane. This reaction is favorable at low temperature, but it is hindered of slow kinetic rates, whereas below a temperature of 270°C, the CO2 conversion is practically 0, and at higher temperatures, 350-400°C, the co-existence of secondary reactions favors the formation of CO. This is the reason why new catalysts and process conditions are continuously being investigated to maximize the methane selectivity, preferably at low reaction temperatures and at atmospheric pressure. Thus, this work is focused on the use of a heterogeneous catalyst Ni/ Zirconia supports modified by rare earth metals such as Lanthanum, tungsten and Yttrium combined to a Dielectric Barrier Discharge plasma. Three catalysts were prepared by a conventional wet impregnation method, using 15 wt% of Ni loading over zirconia supports modified with different promoters. To better define the physical, textural and chemical properties, the catalysts were characterized by the means of BET, XRD, H2-TPR, CO2-TPD. The influence of basicity, Ni crystallite size and the Ni-support interaction on the catalytic activity was clearly evidenced.