Decontamination of heavy metal-contaminated soils by chemical extraction
- Battelle Memorial Inst., Columbus, OH (United States)
- Iowa State Univ., Ames, IA (United States)
Chemical extraction is an emerging remedial technology for the decontamination of soils contaminated with inorganic pollutants such as heavy metals. In this study, various chemicals were evaluated to determine their effectivenesses in removing lead (Pb), copper (Cu), and zinc (Zn) from a heavy metal-contaminated soil. Extraction chemicals tested were nitric acid (HNO{sub 3}), two chelating agents (nitrilotriacetic acid, NTA and ethylenediaminetetraacetic acid, EDTA), and combinations of NTA or EDTA with sodium citrate (NaCit). Solutions of EDTA and EDTA/NaCit were buffered at pH 7.0. Contaminated soil used in this study was silty sand with concentrations of Pb, Cu, and Zn as high as 40,000, 1,500, and 200 mg/Kg, respectively, for soil fractions less than 10 mesh. Maximum removal of Pb were 99.13%, 98.35%, 98.88%, 75.82%, and 68.60% using 1 {und M} HNO{sub 3}, 0.1 {und M} EDTA, 0.1 {und M} EDTA/0.1 {und M} NaCit, 0.1 {und M} NTA, and 0.01 M NTA/0.1 {und M} NaCit, respectively. HNO{sub 3} and EDTA was found to be more effective at removing Cu and Pb than Zn. EDTA/NaCit were slightly more efficient than EDTA alone at the extraction of Pb, Cu, and Zn. NTA and NTA/NaCit were the least effective extractants among those agents tested, especially for Pb extraction. HNO{sub 3} and EDTA/NaCit appear to be the promising extracting agents for the decontamination of heavy metal-contaminated soils. An advantage of using EDTA/NaCit over HNO{sub 3} is that handling/storing of corrosive liquids is minimized.
- OSTI ID:
- 113186
- Report Number(s):
- CONF-940499-; ISBN 1-56590-014-6; TRN: IM9544%%146
- Resource Relation:
- Conference: Federal environmental restoration and waste minimization conference and exhibition, New Orleans, LA (United States), 25-29 Apr 1994; Other Information: PBD: 1994; Related Information: Is Part Of 1994 Federal environmental restoration III and waste minimization II conference and exhibition: Proceedings. Volume 1; PB: 783 p.
- Country of Publication:
- United States
- Language:
- English
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