FIXED-BED PHOTOCATALYSTS FOR SOLAR DECONTAMINATION OF WATER

A solar decontamination process for water was developed using TiO2 photocatalysts supported on silica-based material. The supported catalysts were systematically optimized with respect to catalyst type, catalyst dosage, silica-based support material, particle size, catalyst/support bonding, and calcination temperature. The optimized supported catalysts outperformed an optimized slurry catalyst under identical operational conditions and had a reaction rate four times that of the slurry catalyst. Trichloroethylene (TCE) as a model compound was also used to investigate the impact of solar irradiance, influent concentration, pH value, and hydraulic loading. Supported photocatalysts displayed high light efficiencies over a wide range of weather conditions, an apparent quantum yield of 40% was obtained in a rainy late-afternoon experiment. The complete mineralization of TCE was achieved, and in addition, background natural organic matter (BNOM) in a local surface water did not interfere with the degradation significantly.