DECOMPOSITION OF PERCHLOROETHYLENE AND POLYCHLORINATED-BIPHENYLS WITH FENTON REAGENT

Many of the hazardous waste sites identified by U.S. EPA are contaminated with chlorinated organics such as perchloroethylene (PCE) and polychlorinated biphenyls (PCBs). Since these compounds are toxic to indigenous microorganisms, bioremediation is considered impractical at highly contaminated sites, and a chemical treatment method is often recommended. Fenton's reagent has recently drawn considerable attention because of its ability to decompose a variety of organic compounds. This study has been undertaken to examine the efficacy of Fenton's reagent to decompose PCE and PCBs adsorbed on sand. Results have shown that oxidation by Fenton's reagent can be an effective method to remediate PCE- and PCBs-contaminated soils. Over 90% of PCE was decomposed in 2 h, and over 70% of PCBs were degraded in 3 h. PCE followed the first-order decomposition kinetics with a constant value of 1.65/h, while the PCB degradation appeared to be zero-order with a constant value of 37.6 mg PCB/kg sand/hr at pH 3. Possible byproducts during the oxidation reaction were also examined.