Sonophotocatalytic degradation of trichloroacetic acid in aqueous solution

The degradation of trichloroacetic acid (TCA) in water under ultrasound (US), ultraviolet (UV)/TiO2, and combination of UV/TiO2 and US irradiation was investigated. It was found that the extent of sonophotocatalytic degradation was higher compared with sonolysis or photolysis alone. The influence of operating parameters such as TiO2 concentration, pH values, temperature and dissolved gases on sonophotocatalytic degradation of TCA was studied. Enhancement in the degradation rate has been observed at a higher catalyst loading, a higher temperature and an acidic condition under dissolved oxygen. In addition, the degradation kinetics, mechanism and possible degradation products were discussed in detail.