Direct conversion of gas-glycerol to Allyl alcohol over V, Ti or Nb modified MoFe/KIT-6 oxide catalysts

The porous MoFe/x-KIT-6 (x = V, Nb, or Ti) oxide catalysts with high specific surface area were prepared through in-situ modification and wet impregnation methods for direct conversion of gas-glycerol into allyl alcohol. The modification of V, Nb or Ti on KIT-6 effectively altered and adjusted the mesoporous structure, surface Mo6+/Fe3+ distribution, and surface acid density of the MoFe/x-KIT-6 catalysts, leading to a promotion on the catalytic performance of the MoFe/V-KIT-6 but negative effects on that of the MoFe/Nb-KIT-6 and MoFe/Ti-KIT-6, comparing with the MoFe/KIT-6. The selectivity of allyl alcohol over the MoFe/V-KIT-6 increased to 31.4 % from gas-glycerol (Con. 92 %) most probably through dehydration of glycerol to an intermediate and consecutive reduction, and the yield of allyl alcohol, acrolein, and acetaldehyde reached 58.5 %. Moreover, the MoFe/V-KIT-6 showed improved catalytic stability and good regeneration ability benefiting from the ordered developed mesoporous structure and reduced surface moderate acid density.