The kinetics of degradation of methyl tert-butyl ether (MTBE) by ultrasonic irradiation in the presence of ozone as functions of applied frequencies and applied power are investigated. Experiments are performed over the frequency range of 205-1078 kHz. The higher overall reaction rates are observed at 358 and 618 kHz and then at 205 and 1078 kHz. The observed pseudo-first-order rate constant, k 0 , for MTBE degradation increases with increasing power density up to 250 W L -1 . A linear dependence of the first-order rate constant, k O3 , for the simultaneous degradation of O 3 on power density is also observed. Naturally occurring organic matter (NOM) is shown to have a negligible effect on observed reaction rates.

Oxidation of trichloroethylene (TCE) and tetrachloroethylene (PCE) with various dosages of ozone or ozone plus hydrogen peroxide was studied in laboratory experiments. The results show that hydrogen peroxide accelerates the oxidation of TCE and PCE by ozone. At peroxide‐to‐ozone dosage ratios of >0.7 (w/w), the process appears to be mass transfer limited. High levels of bicarbonate ion in the groundwater significantly decreased the efficiency of TCE and PCE removal by the ozone‐peroxide system, suggesting that softening prior to oxidation may improve the process.

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This article presents the results of a pilot‐scale evaluation of an advanced oxidation process that utilizes hydrogen peroxide and ozone. Treatment efficiency was determined as a function of the hydrogen peroxide‐to‐ozone dosage ratio, ozone dosage, and contact time. The ozone mass transfer characteristics of the process were also investigated. Comparison with other treatment technologies indicates that advanced oxidation can be a cost‐effective treatment process for controlling the common chlorinated organics found in groundwater.