Long-life Supported Molybdenum Oxide Cluster Catalysts for Selective Acetone Hydrodeoxygenation

MoO3 is effective for acetone hydrodeoxygenation (HDO) to propylene, but undergoes severe deactivation mainly due to excessive reduction. This study prepared molybdenum oxide cluster catalysts supported on SiO2 ((NH4)6Mo7O24/SiO2 and H3PMo12O40/SiO2) for selective acetone HDO using polyoxometalates as catalyst precursors. H2-TPR (temperature programmed reduction) and O2-TPO (temperature programmed oxidation) measurements revealed that redox activity for the formation and regeneration of active species was higher than that of MoO3. Reoxidation of the supported molybdenum oxide cluster catalyst by acetone required lower temperatures than MoO3, which allowed suppression of excessive catalyst reduction. Under the optimal reaction conditions, the (NH4)6Mo7O24/SiO2 catalyst achieved a propylene yield of over 75 % and maintained its high catalytic activity for 24 h.