The hydrogenation of maleic anhydride to γ-butyrolactone using mixed metal oxide catalysts in a batch-type reactor

An improved catalytic hydrogenation process for converting maleic anhydride and/or succinic anhydride to γ-butyrolactone uses a novel selective catalyst in a liquid phase operating at high pressure batch-type reactor. The catalysts are composed of palladium, molybdenum and nickel on a silica support of high surface area. This multi-component mixed metal oxide catalyst system in a batch-type reactor is found to be suitable for the hydrogenation of maleic anhydride selectively to γ-butyrolactone. The effects of temperature, pressure and catalyst to reactant ratio are investigated in order to optimize the reaction conditions for better activity, yield and selectivity. A reaction temperature of 220 to 260 °C and pressure of 60 to 80 atm were afforded, the mixed metal oxide catalyst containing nickel, palladium and molybdenum oxide is shown almost 100% conversion of maleic anhydride within 120 min and 56–96% yield of γ-butyrolactone. The hydrogenation of maleic anhydride using this catalyst is not observed by-products and the selectivity of γ-butyrolactone is very high.