Ultrasound as a catalyzer of aqueous reaction systems: the state of the art and environmental applications

The work presented here is aimed to guide environmental researchers and eng ineers in ultrasound-based chemical reaction systems, which are emerging as promising alternatives for the removal of refractory organics in treated e ffluents or natural waters. In accordance, the paper is presented in two pa rts as: (i) an extensive review of aqueous reaction systems catalyzed by ul trasonic pressure waves, with emphasis on basic theories, physical/chemical principles, state of the art, and figures-of-merits of sonochemistry, and (ii) a summary of lab-scale experimental work using ultrasonic reaction sch emes for rendering or catalyzing the destructional removal of organic compo unds by oxidation in the bulk liquid upon hydroxylation. and/or by thermal decomposition in the gaseous bubble. (C) 2001 Elsevier Science B.V. All rig hts reserved.