The search for the most suitable hydrodechlorination catalysts should consider both the C-Cl bond strength in a molecule subjected to reaction and the metal-chlorine bond, which should be neither too strong nor too weak. An improvement of Pd- and Pt-based catalysts can be achieved by alloying with metals which bind chlorine even less strongly, e.g. with gold. Addition of platinum to palladium would also be beneficial because of metal-chloride bond energy considerations. Analogous effects occur in the hydrodechlorination of dichlorodifluoromethane and 1,2-dichloroethane, the molecules characterized by stronger carbon-chlorine bonds.