Methane oxidation in palladium/zeolite catalysts: Facilitating palladium oxide formation and elucidating the reaction mechanism

Pd/zeolite catalysts are a promising alternative to conventional Pd/Al2O3 for CH4 oxidation in wet conditions. Understanding how PdO nanoparticle formation is affected by the Pd loading and the zeolite Si/Al molar ratio as well as the mechanistic CH4 oxidation pathways is vital. This review discusses the current advances in Pd/zeolites for CH4 oxidation, the PdO properties for improved performance, and the underlying reaction mechanism. The effect of the PdO amount, dispersion, and confinement, particularly in highly siliceous zeolites, on the CH4 oxidation performance is examined, followed by a review of computational mechanistic studies.