Kinetics of Hydrogenolysis of Glycerol into 1,2-Propylene Glycol on a Copper Catalyst

Abstract

The kinetics of hydrogenolysis of glycerol to 1,2-propylene glycol on a catalyst containing 60 wt % copper on Al₂O₃ was studied. A reaction scheme for the conversion of glycerol under conditions of catalytic hydrogenolysis was proposed. The forms of kinetic equations for the consumption of glycerol in the main direction to acetol and 1,2-propylene glycol and in side conversion into ethylene glycol were determined. It was found that both of the reactions of glycerol hydrogenolysis have zero and first orders with respect to hydrogen and glycerol, respectively. The apparent activation energies of the main (to acetol and 1,2-propylene glycol) and side (to ethylene glycol) reactions of glycerol conversion are 125 500 ± 200 and 87 500 ± 500 J/mol, respectively. The assumption that the dehydration of glycerol to acetol is a rate-limiting step of the production of 1,2-propylene glycol was substantiated.