Title: Photolysis Improvement of Toluene in 50%TiO<sub>2</sub>/6%WO<sub>3</sub>Sol Solutions Sensitized by Acetone
Abstract: Objectives: The photocatalytic degradation of toluene in a batch mode photoreactor for the purpose of the hazardous waste treatment was investigated. Methods: Kinetic experiments using a low pressure mercury lamp (Lambda Scientific Pty Ltd, 50 Watt) emitting both UV and visible light were performed at <TEX>$31^{\circ}C$</TEX> over toluene concentrations ranging from 10 to 50 mg/l in water with <TEX>$50%TiO_2/6%WO_3$</TEX> (TW) concentration of 1 g/l at a pH of 6. Results: Kinetic studies showed that <TEX>$50%TiO_2/6%WO_3$</TEX> (TW) photocatalyst was highly active in toluene degradation; we observed that 99% of the pollutant was degraded after six hours under visible irradiation; furthermore, we observed that adsorption onto TW catalyst was responsible for the decrease of toluene with pseudo-first order kinetics. It was also found that oxygen as a radical source in the sol medium played a significant role in affecting the photodegradation of toluene, especially with a two-fold elevation. This increase was achieved by a more than four-fold elevation of the photodegradation of toluene in the presence of acetone than without, presumably via an energy transfer mechanism. Conclusions: We concluded that photodegradation in acetone and oxygen molecules along with TW was an effective method for the removal of toluene from wastewater.