Removal of Natural Organic Matter Using Uvc/tio2 Photocatalysis Process Coupled with Coagulation Treatment

The use of standalone titanium dioxide (TiO2) photocatalytic treatment and one that is combined with coagulation process to treat natural organic matter (NOM) from two different water sources (synthetic water containing 10 ppm of humic acid and water samples sourced from Myponga reservoir) is investigated herein. In the combined process, the water samples were treated with a novel composite coagulant prepared from polyaluminium chloride and chitosan, after which the water was filtered and transferred to the photoreactor for further photocatalytic treatment. The water samples were analysed for changes in UV254 Absorbance, Dissolved Organic Carbon (DOC) concentration and trihalomethane formation potential (THMFP). Results showed that chitosan reduced the dose of aluminium required, and TiO2 photocatalytic treatment process coupled with coagulation treatment was able to reduce the duration needed for the photocatalytic removal of natural organic matter while maintaining similar high removal efficiency as standalone TiO2 photocatalysis treatment (>90%). The THMFP was shown to be reduced to low ppb levels (<50 ppb).