Sonochemical degradation of chlorinated hydrocarbons using a batch and continuous flow system

The sonochemical degradation of chlorinated hydrocarbons such as 1,1,1-trichloroethane, trichloroethylene and tetrachloroethylene in aqueous solution was carried out in the batch and continuous flow systems at an ultrasonic frequency of 100kHz under an air atmosphere. In the batch experiment, the rate of degradation follows the order 1,1,1-trichloroethane>tetrachloroethylene>trichloroethylene, and the chlorinated hydrocarbon were readily degraded by ultrasonic irradiation. The experiments in the continuous flow system were performed in the range of volumetric flow rate from 7 to 30 x 10(-3)lmin(-1). The conversion of the chlorinated hydrocarbons at a steady-state of reactor depended on the volumetric flow rate. The yield of Cl(-) (as a measurement of mineralization of chlorinated hydrocarbons) was 70-90% of the chlorine atoms in the parent chlorinated hydrocarbon molecules. From the viewpoint of the scale-up process, the sonochemical degradation of trichloroethylene was simulated in a three stage reactor, and the conversion (>99%) in a third stage reactor was showed the good results that can be satisfied a desired water quality standard.