Byproduct Formation During the Reduction of TCE by Zero-Valence Iron and Palladized Iron

Authors

Liyuan Liang, Oak Ridge National Laboratory
Nic Korte, Oak Ridge National Laboratory
J. D. Goodlaxson, Oak Ridge National Laboratory
Jay Clausen, Locke\heed Martin Energy Systems, inc.
Quintus Fernando, University of Arizona
Rosy Muftikian, University of Arizona

Date of this Version

1997

Comments

Published in Ground Water Monitoring & Remediation Volume 17, Issue 1, Date: February 1997, Pages: 122-127.

Abstract

Trichlorothene (TCE) was reduced with zero-valence iron and palladized iron in zero-head-space extractors. Progress of the reaction in these batch studies was monitered with purge-and-trap gas chromatography and a flame ionization detector. When a 5 ppm initial concentration of TCE reacts with zero-valence iron, approximately 140 ppb of vinyl chloride persists for as long as 73 days. The concentration of vinyl chloride (approximately 10 ppb) remaining with palladized iron is approximately and order of magnitude less than when zero-valence iron is the reductant. These data suggest that volatile byproducts may be under-represented in other published data regarding reduction in zero-valence metals. These results also demonstrate that the reduction of TCE with palladized iron (0.05 percent palladium) is more than an order of magnitude faster than with zero-valence iron. With a 5:1 solution-to-solid ratio, the TCE half-life with zero-valence iron is 7.41 hours, but is only 0.59 hours with the palladized iron.