Effect of the treatment with H3PO4 on the catalytic activity of Nb2O5 supported on Zr-doped mesoporous silica catalyst. Case study: Glycerol dehydration

•The interaction of H3PO4 is higher with Zr than Nb, probably forming Zr(HPO4)2.•This phase showed weak-moderate acid strength related to Brönsted acid sites.•ZrNbP0.2-1c enhanced catalytic results by balance of textural and acid properties.•Strong Lewis acid sites are involved in secondary reactions consuming acetol.