Kinetic studies of gas-phase hydrogenolysis of methyl formate to methanol over copper-based catalyst

Hydrogenolysis of methyl formate was studied at atmospheric pressure over skeletal copper and copper chromite catalysts. Measurements of initial activity, made for the skeletal copper catalyst due to its fast deactivation by fouling, showed that the rates of hydrogenolysis were approximately zero order with respect to methyl formate and had positive order for hydrogen. The activation energy for the reaction was found to be around 54kJ/mol for skeletal copper and 83kJ/mol for the copper chromite catalyst. Methanol had negligible effect on the activity of the reaction in the absence of CO. The kinetics were interpreted using Langmuir-Hinshelwood empirical models and it appears that the rate-determining step involves formation of a surface hemiacetal species, which gives a surface methoxy group and formaldehyde, by reaction with atomic hydrogen adsorbed on adjacent sites.