An experimental study on the design and performance evaluation of alumina based trimetallic catalysts for carbon dioxide reforming of methane (CDRM)

The objective of this investigation is to scrutinize the performance of the catalysts composed of 3 wt.% Ni-3 wt.% Co-3 wt.% Mg supported on γ-Al2O3. The catalysts were synthesized to assess the impacts of varied impregnation techniques, calcination procedures, and reaction temperatures in the context of Catalytic Dry Reforming (CDRM) reactions. Prior to impregnating the metals, the alumina support underwent calcination at distinct temperatures (770°C and 900°C) to prepare it for subsequent metal incorporation. Nickel, cobalt, and magnesium were impregnated onto calcined alumina supports at 3wt% loadings, employing two different methodologies: sequential impregnation and co-impregnation. Catalysts, reduced under pure H2 at 500°C, were employed for the generation of hydrogen and carbon monoxide where methane, carbon dioxide are the reactants. Experiments were conducted at five different temperatures ranging from 600°C to 800°C. Each experiment utilized was performed over 100 mg of freshly reduced catalysts, and the reaction was sustained at a flow rate of 100 ml/min for a duration of 6 hours. Catalyst activities were determined by Gas Chromatography analysis of the reactant and product gas mixture. The outcomes of the performance evaluations revealed that the catalyst, with alumina support calcined at 770°C, subjected to sequential impregnation, and tested at the highest reaction temperature of 800°C, demonstrated notable stability, yielding the highest conversion values of 94.76% and 95.53% for CH4, CO2, respectively, and yielded a product have in H2/CO ratio of 0.97. Analysis of the results underscores the critical influence of calcination temperature, impregnation method, loadings of metals, reaction conditions, and their interplay on catalyst performance.