Two-stage Conversion of Glycerol into Propylene Glycol over Cu/Al2O3 Catalyst
The conversion of 30 % glycerol mixture in ethanol over Cu/Al2O3 catalyst at 493 K/0.1MPa was studied under Ar-H2 flow with different H2 content. It was shown, that 84 % selectivity towards hydroxyacetone is achieved at using 2.5 % H2 concentration in a carrier gas. Then the product obtained at 493 K has been hydrogenated into a propylene glycol at 448 K in pure H2 flow under 1.2 MPa. 89 % selectivity towards propylene glycol was achieved at moderate consumption of hydrogen H2/C3H6O2 = 4 (mol). Two-stage conversion of glycerol into the propylene glycol at different pressure is proposed.