Sonochemical decomposition of organic pollutants in landfill leachate

A method for degradation of organic pollutants in landfill leachate by ultrasound irradiation was presented. Up to 81.12% COD removal efficiency could be obtained using ultrasound irradiation with air aeration, in the presence of NaCl and TiO sub(2). The process variables studied include the ultrasound power input, the initial COD concentration, the initial pH, and the aeration of air. The effects of additional NaCl and the presence of TiO sub(2) inorganic catalyst were also examined. The COD removal of landfill leachate was effectively inhibited by the addition of n-butyl alcohol, which is an efficient OH radical scavenger, but the removal was not complete. It can be suggested that the main sonolysis of landfill leachate proceeds via reaction with OH radicals; a thermal reaction also occurs, although its contribution is small.