In Situ Remediation of Sites Contaminated With Organic Compounds Using Iron Catalyzed Persulfate as an OxidantEPA Grant Number: MA916306
Title: In Situ Remediation of Sites Contaminated With Organic Compounds Using Iron Catalyzed Persulfate as an Oxidant
Investigators: Mohanty, Nihar
Institution: University of Massachusetts - Lowell
EPA Project Officer: Zambrana, Jose
Project Period: January 1, 2004 through December 31, 2005
Project Amount: $101,069
RFA: GRO Fellowships for Graduate Environmental Study (2004) RFA Text | Recipients Lists
Research Category: Academic Fellowships , Engineering and Environmental Chemistry , Fellowship - Engineering
In situ chemical oxidation (ISCO) technologies have been used for degradation of organic compounds in soil and groundwater; however, some commonly used oxidants like the Fenton’s reagent and permanganates have limitations for ISCO applications and therefore cannot be universally applied. Chemical oxidation using iron catalyzed persulfate (ICP) results in the formation of a highly reactive sulfate free radical. Use of ICP potentially represents an innovative technology for the in situ treatment of soils and groundwater contaminated with organic compounds including the energetic compounds that exist at many Department of Defense sites. Based on preliminary experiments conducted at the University of Massachusetts–Lowell Civil Engineering Laboratory, ICP appears to be a superior ISCO oxidant. The objective of the proposed laboratory-scale study is to determine the full range of capabilities and limitations of the use of ICP for the destruction of organic compounds including energetic compounds (RDX and HMX) in soil and groundwater.
Experiments are being conducted on select contaminant(s) to study interactions between the contaminant, the oxidant, ferrous and ferric forms of iron, and the catalyst. Several catalysts, including modified cyclodextrins, will be evaluated for efficiency of removal of select contaminant(s). Aqueous and soil samples of the target contaminant will be prepared in the laboratory. Experiments will be conducted in the laboratory under controlled temperature and conditions. Analysis of contaminants in soil and water will be conducted in accordance with appropriate EPA methods. Iron, pH, persulfate ion, cyclodextrins/chelating agent, and target contaminants will be monitored during the experiments. Kinetic data analysis will be conducted to estimate rate constants. It is postulated that sulfate free radicals could be effective in degrading target organic contaminant(s) in the presence of iron as a catalyst. The effectiveness of the oxidation process is expected to be enhanced by addition of a chelating agent with iron. Additionally, availability of iron from soil at a field site will be evaluated for in situ oxidation. Preliminary experiments are being carried out jointly at the Environmental Laboratory at University of Massachusetts–Lowell and at EPA’s laboratory in Chelmsford, MA.