Cu–Al composite oxides: a highly efficient support for the selective oxidation of glycerol to 1,3-dihydroxyacetone

Abstract

A series of Au catalysts supported on Cu–Al composite oxides were prepared and applied for the selective catalytic oxidation of glycerol to 1,3-dihydroxyacetone (DHA) in base-free conditions. The optimal Au/CuAlO-3 catalyst (the molar ratio of Cu/Al was 5 : 1) exhibited the best performance, and reached the glycerol conditions of 76.7% and DHA selectivity of 97.3% under the optimized reaction conditions. The high catalytic activity of the Au/CuAlO-3 catalyst correlated to the large concentration of surface-active oxygen species, the low reduction temperature of the support, the small size of Au nanoparticles (NPs) and the interactions between Au NPs and the support. This work demonstrates that Cu–Al composite oxides are promising supports for selective catalytic oxidation of glycerol to DHA, and may offer guidelines for designing efficient support for the selective conversion of glycerol to other high value-added products.