Photocatalytic Degradation of Dissolved Organic Matter in the Ground Water Employing TiO2 Film Supported on Stainless Steel Plate

The Taman Palem Residences, Cengkareng, Indonesia has a groundwater problem as a main sources of drinking water in the area due to yellowish brown colour of the water, that may come from dissolved organic matter (DOM), humic substances. Photocatalytic degradation using TiO2 coated on a stainless
steel plate (8 x 8 cm) to degrade the dissolved organic matter was studied. Groundwater samples were collected at 150 m deep from Taman Palem Residences. The TiO2 catalyst was
made from deep coating in a sol-gel system of titanium (IV) diisopropoxidebisacetylacetonate (TAA) precursor and immobilized at stainless steel plate (8 x 8 cm), followed by calcination at 525o C. Two catalyst sheets were put in batch reactor containing groundwater. The groundwater containing DOM were irradiated by UV black light at varying initial pH values i.e 5, 7 and 9. Sampling of solution was taken at the interval time of 0, 1, 2, 4, and 6 hours. DOM residu in water before and after irradiation were measured by spectrophotometer UV-Vis at 300 nm. Photocatalytic degradation of DOM was greater in acid solution than in basic
solution. The determination of intermediate degradation products by HPLC revealed that oxalic acid was detected consistently.

Keywords : Dissolved organic matter (DOM), groundwater, photocatalytic, TiO2