Gas-phase hydrogenation of maleic anhydride to γ-butyrolactone at atmospheric pressure over Cu–CeO 2–Al 2O 3 catalyst

Abstract

Cu–CeO 2–Al 2O 3 catalyst, prepared by co-precipitation method, was investigated for the gas-phase hydrogenation of maleic anhydride (MA) to γ-butyrolactone (GBL) at atmospheric pressure and the catalyst deactivation was also studied. Effects of catalyst composition, reaction temperature, and liquid hourly space velocity (LHSV) of raw material on the catalytic performance of Cu–CeO 2–Al 2O 3 catalyst were investigated. The catalyst (molar ratio of Cu:Ce:Al = 1:1:2) showed better catalytic performance, in which both the conversion of MA and the selectivity of GBL kept 100% within two hours under the reaction conditions of 6 mL catalyst, 0.1 MPa, 220–280 °C, 30 mL min −1 H 2, 0.6 h −1 LHSV of 20 wt.% MA/GBL. As for Cu–CeO 2–Al 2O 3 catalyst, smaller crystallite size of Cu and higher Cu surface area are favorable to increase its catalytic performance. The deactivation of Cu–CeO 2–Al 2O 3 catalyst is due to formation of the compact wax-like deposition on the catalyst surface, which is probably ascribed to the strong adsorption of succinic anhydride and then polymerization on the catalyst surface. The catalytic performance of the regenerated catalyst can be recovered completely by the regeneration method of N 2–air–H 2 stage treatment.