Hydrodesulfurization on Transition Metal Catalysts: Elementary Steps of C-S Bond Activation and Consequences for Bifunctional Synergies

HDS on S-covered transition metals occurs on exposed metal sites and exhibit mechanistic features for C-S bond activation that are analogous to those for C-C and C-O bond activations. Bifunctional enhancements in hydrogenation rates depend on the formation of reactant-derived molecular H-carriers, which diffuse to sites that cannot dissociate H₂.