Ultrasonic degradation of 2:4:6 trichlorophenol in presence of TiO2 catalyst

The degradation of trichlorophenol has been studied at different intensities of irradiation using ultrasonic horn by changing the power input to the system. Effect of presence of catalyst TiO2 and concentration of catalyst on the degradation rates has also been investigated. The rates of degradation are found to be higher at higher intensities in the absence of catalyst but reverse trend is observed in the presence of catalyst. Adsorption and desorption characteristics of trichlorophenol on TiO2 catalyst have been examined. The catalyst enhances the rates of degradation but it also adsorbs some amount of TCP during the degradation process protecting it from ultrasonic degradation. Thus it is essential to consider the adsorption and desorption kinetics to get proper estimates of the degradation rates when the rates of degradation of TCP are calculated by analyzing the residual concentration of the compound in the liquid. The degradation of the pollutant seems to take place in the liquid only and that too only after desorption of the same from the solid particles. Solid particles seem to play a physical role in the overall degradation scheme, providing additional surface cavitation. (C) 2001 Elsevier Science B.V. All rights reserved.