Support effects in the aqueous phase reforming of glycerol over supported platinum catalysts

Aqueous phase glycerol reforming was studied for a set of Pt catalysts supported on gamma-Al2O3, SiO2 and amorphous silica-alumina (ASA) with varying alumina concentrations.The main products at 225 degrees C under 29 bar N-2 pressure for a feed of 20 wt.% glycerol are H-2, CO2 and C-1-C-3 alkanes, 1,2-propanediol, hydroxyacetone and C-1-C-3 monoalcohols are the products in the liquid phase. Boehmite formation is observed for the gamma-Al2O3 and ASA supported catalysts. The higher the Al concentration of ASA, the higher the amount of boehmite. Especially at low Al concentrations, the presence of boehmite is limited and silica leaches from the ASA support under reaction conditions. The increased surface acidity as a result of the presence of boehmite leads to increased hydroxyacetone formation (glycerol dehydration) and 1,2-propanediol (hydroxyacetone hydrogenation) formation. The activity of boehmite supported Pt for hydrodeoxygenation and reforming reactions is higher than that of gamma-Al2O3 and SiO2 supported Pt. (c) 2012 Elsevier B.V. All rights reserved.