Methane combustion over Pd supported on MCM-41

This work aimed at studying the feasibility of using mesoporous molecular sieves (MCM-41) as supports for palladium-based catalysts for methane combustion. The effects brought about by the chemical composition as well as by the presence of cerium and lanthanum were investigated. The MCM-41 structures were found to be thermally stable under air: the MCM-41 is stable until 1273 K while the [Al]-MCM-41 resists up to 1173 K. Silicate-based catalysts are more active than the aluminosilicate-supported Pd samples; while no changes were observed on the structure of the materials during the catalytic test, it was found that the addition of La and Ce decreased their activity. The catalytic activity was correlated with the hydrophobic character of the supports, and with the smaller temperature of PdO reduction presented by the catalysts.