Kinetic studies of vapor-phase hydrogenolysis of butyl butyrate to butanol over Cu/ZnO/Al₂O₃ catalyst

Kinetic investigations on the hydrogenolysis of butyl butyrate to butanol over a commercial Cu/ZnO/Al₂O₃ catalyst were conducted. The catalytic measurements at atmospheric pressure showed that the rate of hydrogenolysis was approximately 0.67 order with respect to butyl butyrate and had a positive effect for hydrogen. The activation energy of this reaction was measured to be about 62 kJ/mol, and D₂ isotope studies corroborated that the hydrogenolysis of butyl butyrate proceeds via dissociative adsorption of ester producing C₃H₇CO and C₄H₉O fragments. In addition, kinetic studies, interpreted by applying the basis of the Langmuir-Hinshelwood model, suggested that the rate-determining step involves the dissociative adsorption of butyl butyrate. Finally, the rate expression derived in this study provided precise and reasonable fitting results, and an activation energy close to the value obtained from the power law equation.