Admicelle-Catalyzed Reductive Dechlorination of Perchloroethylene (PCE) by Zero Valent Iron

Background/Need:

Chlorinated solvents are a major groundwater contaminant at industrial sites, U.S. Department of Energy facilities, and military installations. Recent discovery of using zero valent iron (ZVI) as permeable barriers to degrade chlorinated solvents dissolved in groundwater has attracted great attention. Numerous researches on using ZVI for groundwater remediation have been focused on increasing the degradation rate constant of chlorinated solvents. However, most of them involve in coating the metals with noble metals such as Pt or Pd. Thus a search for an inexpensive, yet effective material, to enhance the rate of degradation of chlorinated solvents becomes more imminent.

Objectives:

The objectives of this research are to further study a novel observation made by the PI on enhanced perchloroethylene degradation by ZVI under the catalysis of a cationic surfactant hexadecyltrimethylammonium (HDTMA). The influence of surfactant chain length of several quaternary ammonium surfactants, the surfactant coverage and the surfactant surface configuration on ZVI, the initial PCE concentrations, and initial solution pH and ionic strength on PCE reduction kinetics will be studied in batch scale. Column experiments will be conducted as a function of initial PCE concentrations and contaminant injection rates to verify the batch results and to provide further justification for future pilot scale and/or field tests.