Study on the reaction pathway in the vapor-phase hydrogenation of biomass-derived diethyl succinate over CuO/ZnO catalyst

The reactivity of biomass-derived diethyl succinate and its main reaction intermediates was separately investigated in a fixed-bed reactor over CuO/ZnO catalyst, and some interesting results were obtained. Ethyl 4-hydroxybutyl succinate as an intermediate of diethyl succinate hydrogenation reaction was first detected, and it could be converted to 1,4-butanediol or polyesters. Additionally, propanol and butanol are mainly derived from 1,4-butanediol rather than gamma-butyrolactone. A comprehensive reaction pathway for the hydrogenation of diethyl succinate is proposed, which is significant for the design of new catalytic formulations. A CuO/ZnO + HY admixed catalyst exhibiting excellent performance was prepared according to the proposed reaction pathway.