Computational And Experimental Sonochemistry

Sonochemistry is an environmentally friendly area of chemistry where chemical reactions are induced by ultrasound waves in the frequency range of 201000 kHz. Sonochemistry is one of the innovative advanced oxidation processes in which hydroxyl radical and other reactive species are generated through acoustic cavitation phenomenon. The implosion of bubbles creates hot spots with temperatures as high as 5000 K, pressures up to 1000 atm and cooling rates in excess of 1010 K/s. These extraordinary conditions are responsible for a variety of chemical and physical effects, i.e. production of free radicals, emission of light (sonoluminescence) and generation of shock waves. In this paper, a computational study based on acoustic cavitation model for reactive bubbles has been used for stating the conditions inside the collapsing bubbles and then approaching the mechanism of free radical production in aqueous sonochemistry. After this, experimental results on sonochemical oxidation of several kinds of organic pollutants have been presented and discussed on the basis of the computational results.