Removal of organic contaminants from water using sonolysis

摘要

Recently it has been shown that sonolysis (sonochemical or ultrasonic destruction) can destroy organic contaminates in water (1,2,3,4,5,6,7,8,9,10,11). In this method, the liquid is irradiated with sound waves generated from an ultrasonic source. When the sound waves pass through a liquid, they create cavities due to oscillating pressures. The dissolved gases and vapors in the bulk solution can diffuse into these cavities. These cavities grow in size and ultimately implode, generating temperatures of about 5200 K inside the collapsing cavity and about 1900 K in the interfacial region between the solutuion and the collapsing bubble (1). The destruction of organic pollutants can occur via several mechanisms, as shown in Figure 1. The organic pollutant and water vapors can diffuse inside the cavity and undergo pyrolysis type reactions during the implosion. Free radicals (OH~*, H~*, O~*, HO_2~*) formed due to the splitting of water molecules(2) may react with the organic in the interfacial region or in the bulk solution.