Role of the support and pseudo-liquid phase in the Phosphotungstic Heteropolyacid (photo)catalytic activity

Catalytic and photocatalytic tests for propene hydration to 2-propanol were successfully carried out by using binary materials obtained by supporting a Keggin or Wells-Dawson heteropolyacids via impregnation method to commercial SiO2 or TiO2. (Photo)catalytic hydration was studied in gas-solid regime by using a continuous (photo)reactor working at atmospheric pressure and 80 °C. The alcohol was the main product. The acidity of the cluster accounts for the catalytic role, whereas both the acidity of the cluster and the oxidant ability were responsible for the increase of the reaction rate of the photo-assisted catalytic reaction. Moreover, the presence of a photoactive semiconductor support showed a beneficial effect to enhance the reactivity of the binary material.