Optimization of structured cellular foam-based catalysts for low-temperature carbon dioxide methanation in a platelet milli-reactor

Here, we present a preliminary study to choose a catalyst with enough catalytic activity at temperatures below 250 °C, in order to study heat transfer in a platelet milli-reactor (PMR) with an infrared camera and a commercial window inserted on the top of our reactor that only withstands a maximal temperature of 250 °C. The higher methane productivity of foam catalysts compared to powder catalysts was revealed. Foam catalysts, all impregnated with the same amount of active phase (Ni + Ru) and with different coatings, were compared to SiC only impregnated with Ni + Ru. The different coatings studied were: carbon nanofibers (CNF), ceria–zirconia (CZ) and the combination of both. Both CNF and CZ washcoats were able to increase the low specific surface area of the SiC foam. Moreover, the presence of ceria–zirconia was proven to be essential for ensuring high methane productivities. The catalyst combining both CNF and CZ showed the best results.