Beta zeolite supported sol-gel TiO2 materials for gas phase photocatalytic applications

Beta zeolite supported sol-gel TiO2 photocatalytic materials were prepared according to a sol-gel route in which high specific surface area Beta zeolite powder was incorporated into the titanium isopropoxide sol during the course of the sol-gel process. This led to an intimate contact between the zeolite surface and the TiO2 precursors, and resulted in the anchorage of large amounts of dispersed TiO2 nanoparticles and in the stabilization of TiO2 in its anatase form, even for high TiO2 wt. contents and high calcination temperatures. Taking the UV-A photocatalytic oxidation of methanol as gas phase target reaction, high methanol conversions were obtained on the Beta zeolite supported TiO2 photocatalysts when compared to bulk sol-gel TiO2, despite lower amounts of TiO2 within the photoactive materials. The methanol conversion was optimum for about 40 wt.% TiO2 loading and calcination temperatures of 500-600 °C.