W-V-O bronzes, catalysts for the transformation of glycerol into acrylic acid

In this paper we report about the one-step transformation of glycerol into acrylic acid, catalyzed by W-V-O mixed oxides with hexagonal tungsten oxide structure. The reaction requires two different catalyst functionalities, i.e., an acid one, which is inferred by WO3, aimed at the dehydration of glycerol into acrolein, and an oxidizing one, given by the V-sites incorporated inside the WO3 lattice, aimed at the oxidation of acrolein into acrylic acid. WO3 (W-O bronze) was very active and moderately selective in acrolein formation, but yielded only traces of acrylic acid. The incorporation of increasing amounts of V-atoms inside the hexagonal tungsten oxide structure favoured the consecutive oxidation of acrolein into acrylic acid. The selectivity to acrylic acid was affected by the W/V atomic ratio.