CeO2 promoting allyl alcohol synthesis from glycerol direct conversion over MoFe/CeO2 oxide catalysts: morphology and particle sizes dependent

MoFe-N, MoFe/c-CeO2, MoFe/p(1)-CeO2, and MoFe/p(2)-CeO2 (where N, c, and p stand for non-supported, nanocube, and nanoparticle) oxide catalysts were designed for gas-glycerol direct catalytic conversion into allyl alcohol. The catalysts also were characterized by XRD, TEM, BET, H-2-TPR, and NH3-TPD. Mo-Fe oxides were highly dispersed on the surface of c-CeO2 and p-CeO2 supports, different with the MoFe-N consist of crystalline Fe-2(MoO4)(3) and Fe2O3 crystalline phase. The support effect and special natural property of CeO2 significantly improve the allyl alcohol selectivity from gas-glycerol over MoFe/CeO2. The p-CeO2 with low particle sizes and crystalline degree was superior to high-crystalline nanocube c-CeO2 to promote its interaction with the MoFe oxide active components, and improve the surface acid site concentration and reducibility of MoFe/CeO2 as well as catalytic activity and stability for allyl alcohol synthesis from gas-glycerol without any extra hydrogen donors. Over the MoFe/p(2)-CeO2, the glycerol conversion reached 97.1%, and the selectivity of allyl alcohol, enthanal, propanoic acid, and acrylic acid were 23.3%, 8.6%, 12.6%, and 7.8%, respectively, yielding allyl alcohol of 22.6%.