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 525°C. Two catalyst sheets were put in batch reactor containing groundwater. The ground water 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. (author)