Perchloroethylene (PCE) oxidation by percarbonate in Fe2+-catalyzed aqueous solution: PCE performance and its removal mechanism

The performance of Fe2+-catalyzed sodium percarbonate (SPC) stimulating the oxidation of perchloroethylene (PCE) in groundwater remediation was investigated. The experimental results showed that PCE could be completely oxidized in 5 min at 20 degrees C with a Fe2+/SPC/PCE molar ratio of 8/8/1, indicating the effectiveness of Fe2+-catalyzed SPC oxidation for PCE degradation. Fe-catalyzed SPC oxidation was suitable for the nearly neutral pH condition, which was superior to the conventional Fenton oxidation in acidic condition. In addition, the investigations by using hydroxyl radical scavengers and free radical probe compounds elucidated that PCE was degraded mainly by hydroxyl radical (HO center dot) oxidation in Fe2+/SPC system. In conclusion, Fe2+-catalyzed SPC oxidation is a highly promising technique for PCE-contaminated groundwater remediation, but more complex constituents in groundwater should be carefully considered for its practical application. (C) 2014 Elsevier Ltd. All rights reserved.