Comparative analysis of the photocatalytic removal of methylene blue and pyrene on TiO2 and WO3/TiO2 particles

Abstract

This study investigated the performance of ultraviolet (UV) light active TiO2 and UV-visible light active WO3/TiO2 nanoparticles coated on zeolite for degrading organic pollutants such as methylene blue and pyrene. Using glass dishes for the batch photocatalytic removal experiments of the organic pollutants, the removal efficiencies of methylene blue and pyrene by two different photo catalytic particles coated on natural zeolites were evaluated. The results showed that the TiO2 and WO3/TiO2-coated zeolites are excellent photoactive materials providing enhanced removal function (>95% removal efficiency of methylene blue) under UV and UV-visible light irradiation, respectively. However, lower efficiencies were observed for both TiO2 and WO3/TiO2 powders and TiO2 and WO3/TiO2-coated zeolite in removing pyrene in aqueous solution under UV and visible light irradiation. In column tests, both TiO2 and WO3/TiO2-coated zeolites have shown only measurable pyrene removal efficiency of -50% under UV irradiation. This could be due to the negligible adsorption of pyrene on the photocatalytic reaction sites both for TiO2 and WO3/TiO2-coated zeolite. Nevertheless, this study revealed the potential utility of photocatalytic particles in improving urban water quality, which can be utilized in the form of the surface component for various urban infrastructures.