Application of ultrasonic irradiation for the degradation of chemical contaminants in water
- Creators
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Hoffmann, Michael R.
- Hua, Inez
- Höchemer, Ralf
Abstract
The sonochemical degradation of a variety of chemical contaminants in aqueous solution has been investigated. Substrates such as chlorinated hydrocarbons, pesticides, phenols, explosives such as TNT, and esters are transformed into short-chain organic acids, CO_2, and inorganic ions as the final products. Time scales of treatment in simple batch reactors over the frequency range of 20 to 500 kHz are reported to range from minutes to hours for complete degradation. Ultrasonic irradiation appears to be an effective method for the rapid destruction of organic contaminants in water because of localized high concentrations of oxidizing species such as hydroxyl radical and hydrogen peroxide in solution, high localized temperatures and pressures, and the formation of transient supercritical water. The degradation of chemical compounds by acoustic cavitation is shown to involve three distinct pathways: 1) oxidation by hydroxyl radicals, 2) pyrolytic decomposition and 3) supercritical water oxidation. Detailed reaction mechanisms for the degradation of p-nitrophenol, carbon tetrachloride, parathion, p-nitrophenyl acetate and trinitrotoluene are presented.
Additional Information
© 1996 Elsevier Science B.V. Received 8 May 1996. Financial support for much of the research described in this paper was provided by the Advanced Research Projects Agency. ARPA, (Grant # NAV 5HFMN N0001492Jl901) through the Office of Naval Research. ONR, and by the Electric Power Research Institute. EPRI, (Contract # RP 8003-37). This support is gratefully acknowledged.Additional details
- Eprint ID
- 59520
- Resolver ID
- CaltechAUTHORS:20150814-081852058
- Advanced Research Projects Agency (ARPA)
- Office of Naval Research (ONR)
- NAV 5HFMN N0001492J1901
- Electric Power Research Institute (EPRI)
- RP 8003-37
- Created
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2015-08-14Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field