ADSORPTION AND PHOTOCATALYTIC DEGRADATION OF AQUEOUS SOLUTION OF POLAR ORGANIC POLLUTANTS

This study examines the adsorption and the photodegradation of isopropanol and its degradation intermediate, acetone, as a polar organic pollutant. Both isopropanol (100 mg/L) and formed acetone are shown to be effectively photodegraded in aqueous suspensions of 2g/L TiO2. It was found that dark adsorption isothermal of isopropanol on the surface of TiO2 was unfavoured process, which suggesting that the photodegradation reaction occurred in the bulk solution (homogeneous) rather than on the surface (heterogeneous) of the photocatalyst. In addition, homogeneous reaction is further confirmed by the decrease of the degradation rate of isopropanol in presence of 1x10-4 M tetranitromethane (TNM) which is effectively eliminating the formation of free OH• radicals in the bulk solution. Under the studied conditions, the parent isopropanol and its degradation product, acetone, were completely degraded from aqueous solution in about 2.5 -5.5 h.