Performance of ZrO2-supported Nb- and W-oxide in the gas-phase dehydration of glycerol to acrolein

► W-, Nb-, and W-Nb-oxide on monoclic zirconia dehydrate glycerol to form acrolein. ► Brønsted acidic W and Nb sites are active and selective for acrolein formation. ► Deactivation occurs due to adsorption of heavy hydrocarbons and coke on the catalyst. ► Regeneration in air is effective, restoring both the activity and the selectivity. ► Co-feeding oxygen with glycerol extends the lifetime of the catalyst.