A spectroscopic study for the photocatalytic oxidation of propane over different types of TiO2

The photocatalytic selective oxidation of propane was investigated by in-situ Fourier transform infrared spectroscopy under the illumination of UV light. Two different commercially available TiO2 photocatalysts were applied; UV-100 and P25. The characterisation data showed significant differences between the two samples; such as phase composition, texture properties, -OH surface density, and the presence of contaminations. P25 (the mixed rutile-anatase phases) showed better adsorption for the reagents and even small quantity of products were observed in dark. However, UV-100; the pure anatase phase with high surface area, exhibited 3-4 times higher photocatalytic activity than P25. Moreover, it was observed that on a similar propane conversion level, the selectivity % of acetone was almost four times higher over P25 than UV-100. Finally, upon mixing UV-100 with rutile, it was observed that the acetone selectivity was improved extensively.