W-Nb-O oxides with tunable acid properties as efficient catalysts for the transformation of biomass-derived oxygenates in aqueous systems

[EN] W-Nb-O oxide bronzes, prepared hydrothermally, have been characterized and studied as catalysts for both the gas-phase dehydration of glycerol and the liquid-phase selective condensation of light oxygenates derived from primary treatments of biomass (a mixture containing acetic acid, ethanol, propanal, hydroxyacetone and water). By controlling the nominal composition of the catalysts, it is possible to tune their textural and acid properties (concentration and nature of acid sites) to selectively produce acrolein from glycerol or C-5-C-10 hydrocarbons (with low O contents and with high yields) from light oxygenates. Interestingly, these catalysts are stable when working in gas phase reactions and they are re-usable, with high resistance to leaching, when working in aqueous media.