CO2 Methanation over Combustion-Synthesized Nickel-Supported Zirconia Catalyst: A Study on Catalyst Performance, Optimization and Stability

Abstract

CO2 methanation offers a sustainable approach to mitigate climate change by converting CO2 into valuable CH4, aligning with global decarbonization goals. This study focuses on the synthesis and evaluation of Ni/ZrO2 catalysts prepared via the combustion method, varying the glycine-to-nitrates ratio (ɣ= 0.5, 1, 1.5, 2, 2.5, 3) and the Ni loading (x=10%, 20%, 30% and 40%). Among these, the 20NiZr-0.5 catalyst achieved the highest CO2 conversion of 81% at 400oC. Further optimization of reaction performance identified that the 30NiZr-0.5 catalyst and a gas hourly space velocity (GHSV)= 30,000 mL/g.hr as the most efficient configuration, achieving 90% CO2 conversion at 350oC and demonstrating stability over 5 days. All prepared catalysts were characterized using BET, SEM and XRD and TGA to analyze surface area, morphology, crystallinity and stability. However, these analyses did not clarify the observed differences in catalytic behavior and performance. Future studies will employ additional chemical characterization techniques like CO2 & H2-TPD, XPS and H2-TPR to investigate surface mechanisms and better understand the factors influencing catalyst performance.