Hydrogenolysis of glycerol to propanediol using co-based catalysts

Abstract

This work was carried out to prepare the supported Co-based catalysts by the impregnation method for glycerol hydrogenolysis in aqueous phase. The investigated parameters were types of support (Al2O3, HZSM5 and AlMCM-41), types of metal (Co, Mo and CoMo), weight ratio of catalyst to glycerol (15-30 mg/g glycerol), metal loading (2.5-20 wt.%) and the reaction conditions including temperature (100-220 °C), H2-pressure (3-9 MPa) and reaction time (3-9 h). The results demonstrated that the catalytic activity of catalysts depended on the acidity of the utilized catalyst, specific surface area and pore volume. Strong-strength acid sites exhibited a better activity for glycerol conversion and effected significantly on the product selectivity. Among as-prepared catalysts, the 5 wt.% Co/HZSM5 catalysts exhibited the highest activity of glycerol hydrogenolysis. It gave the maximum conversion of glycerol of 42% and the maximum yield of the desired products including acrolein, 1,2-PDO and 1,3-PDO of 1, 8 and 5%, respectively, in the presence of the weight ratio of supported Co/HZSM5 catalysts to glycerol of 20 mg/g under the reaction condition of 180 °C, 7 MPa H2-pressure and 6 h reaction time.