Perchloroethylene (PCE) Removal
Water Quality Control
Published Online: 15 JUL 2005
Copyright © 2005 by John Wiley & Sons, Inc.
How to Cite
Inniss, E. C. 2005. Perchloroethylene (PCE) Removal. Water Encyclopedia. 299–301.
- Published Online: 15 JUL 2005
Perchloroethylene (C2Cl4) or PCE, an industrial solvent and common groundwater contaminant, can be degraded by several means, both biological and chemical. Its recalcitrance in the environment has been due in part to the fact that initial biological degradation must be a reduction of this highly oxidized compound, sequentially replacing each of the chlorines with hydrogen through the use of dehalogenase enzymes. Once reduced, dechlorination products of PCE may be further transformed by either reductive or oxidative pathways. The biological oxidation of the lesser chlorinated ethylenes requires particular oxygenase enzymes that perform cometabolic chemistry on the carbon–carbon double bond. Similarly, chemical transformation of PCE can be by either reduction or oxidation. The chemical reductive dechlorination process typically occurs using zero valent metals and is very similar to the biological process. Oxidation of the compound requires a strong chemical oxidant, such as potassium permanganate, or photooxidation using a titanium dioxide catalyst, which also attacks the carbon–carbon double bond of the chlorinated ethylene.
- reductive dechlorination;
- cometabolic oxidation;
- zero valent metals;
- photocatalytic oxidation;
- potassium permanganate oxidation