HYDROGENOLYSIS OF DIMETHYL SUCCINATE ON COPPER-BASED CATALYSTS

The gas-phase hydrogenolysis of dimethyl succinate (DMS) has been stud ied over a series of copper-based catalysts at a temperature of 513 K and a pressure of 500 kPa. Using copper chromite and copper on silica, gamma-butyrolactone (GBL) and methanol were formed in the first step, while GBL reacted further to tetrahydrofuran (THF) and water. Over co pper zinc oxide catalysts, THF was mainly formed in a parallel reactio n directly from DMS. Additionally, the steam reforming of methanol occ urred over these catalysts. No catalyst deactivation with time-on-stre am could be detected. but exposure to DMS significantly decreased the copper surface area of all catalysts. The area specific rate for the r eaction of dimethyl succinate to gamma-butyrolactone over copper zinc oxide was one order of magnitude higher than over the other catalysts. The most active catalyst for the subsequent reaction of GBL to tetrah ydrofuran was found to be copper chromite. The reaction rates could be described by simple kinetic equations based on a reaction network.