Hydrogenolysis of Glycerol to 1,2-Propanediol and Ethylene Glycol over Ru-Co/ZrO2 Catalysts

A series of ZrO2 supported Ru-Co bimetallic catalysts were prepared and evaluated for the hydrogenolysis of glycerol. The Ru-Co/ZrO2 bimetallic catalyst combines the advantages of both Ru and Co, exhibiting high activity and good selectivity to 1,2-propanediol. The X-ray diffraction (XRD) and TEM results show that higher calcination temperature leads to lower reducibility of cobalt oxides and larger metal particle size, which is responsible for the decrease of glycerol conversion. Increasing the reduction temperature causes an inhibition effect on the catalytic activity, but it is beneficial to promote the 1,2-propanediol selectivity. The low temperature (<300 °C) reduction can prevent the growth of metal particles, resulting in higher activity. Co oxide is an important component for the good performance of Ru-Co/ZrO2. The reaction temperature, hydrogen pressure, and glycerol concentration have significant effects on the catalytic performance of the Ru-Co/ZrO2 catalyst.