Enhanced performances of grafted VOx on titania/silica for the selective photocatalytic oxidation of ethanol to acetaldehyde

In this work gas phase photocatalytic selective oxidation of ethanol to acetaldehyde was studied with directly fluidizable photocatalysts made of grafted VOx on titania/silica in presence of phosphors as light carriers to test their performances in the photocatalytic system. The presence of VOx species anchored on TiO2/SiO2 enhanced ethanol conversion up to 66%, with acetaldehyde selectivity higher than 99%. The performances of V-based sample at 11 wt% of TiO2 supported on fluidizable support were higher than those evaluated when nano-TiO2 powder is used as support. Moreover, the photocatalytic conversion of ethanol was further increased in presence of phosphors as light carriers. From the obtained results, it is concluded that by preparing VOx based catalyst through grafting method allows a dramatic enhance in the productivity of acetaldehyde, even when the concentration level of alcohol at photoreactor inlet is increased.