Enhanced plasma-assisted CO2 methanation on Ru/CeO2 catalysts

Methanation process utilizes CO₂ as a carbon feedstock for synthesizing energy carriers and value-added chemicals. The combination of methanation with plasma-catalysis has emerged as a promising avenue for the electrification of power-to-gas technologies, representing a significant development in the transition to sustainable energy systems. The present study investigates the impact of low 5 % mol Ru loading on CeO 2 , focusing in the role of the metal in comparison to Ni and the metal-support interactions examined using CeO 2 with different structures (nanoneedles, nanopowder) and Ru dispersion within the support. The catalyst Ru/NN with nanoneedles of ceria achieved CO₂ conversion of 70 % and CH₄ selectivity of 99 % at 1CO₂/4H₂, WHSV of 30 L h −1 g cat-1 , 12 kg CO2 kg cat-1 h −1 and plasma input power of 8.9 W. The enhanced plasma-catalytic activity of Ru/NN can be attributed to the increased effective H 2 dissociation, beneficial physicochemical and electrical properties attributed to the choice of support and optimal metal-support interaction. The lower dielectric capacitance calculated for this catalyst is the result of reduced charge storage and a faster response to the applied electric field. This produces less intense microdischarges and a more stable and uniform plasma environment. • Ru/CeO 2 catalysts application in plasma-assisted CO 2 methanation. • Effect of metal and metal-support interactions have been studied. • 5 % mol Ru/CeO 2 nanoneedles maximized CO2 methanation • Physicochemical and electrical properties affect the activity. • Lower dielectric capacitance produces a more stable and uniform plasma.