Ferric complexes as catalysts for {open_quotes}Fenton{close_quotes} degradation of 2,4-D and metolachlor in soil
Abstract
Fenton-type reactions of hydrogen peroxide with Fe compounds generate bydroxyl radical (OH{center_dot}) or other reactive species and are potentially useful for degrading organic contaminants in soil. The use of simple Fe salts is limited, however. This study investigated certain pH 6-soluble Fe(III) complexes (Fe-L, where L is an organic tigand) as catalysts for degradation of herbicides 2,4-dichlorophenoxyacetic acid (2,4-D) and metolachlor (2-chloro-N-[2-ethyl 6-methylphenyl]-N-[2-methoxy-l-methylethyl]acetamide). Reactions were carried out in 1:1 aqueous suspensions of a topsoil (15.7 g kg{sup -1} organic C) at the natural pH of 5.7 with herbicides at concentrations representative of a spill (2-3 g kg{sup -1} about 0.01 mol kg{sup -1}). The two herbicides had contrasting sorption behavior in that 2,4-D was mostly in solution, whereas metotachlor was mostly sorbed. The best results were obtained using Fe-nitrilotriscetate (NTA) or Fe-hydroxyethyleniminodiacetate (HEIDA) at 0.01 mol kg-{sup -1} and [H{sub 2}O{sub 2}]{ge} 0.5 mol kg{sup -1}. The gallic acid complex was less effective. In 3 h,{sup 14}C-labeled 2,4-D was quantitatively dechlorinated and partially (15-30%) converted to {sup 14}CO{sub 2}: metolachlor was 93% transformed and 29% dechlorinated. Controls using free ligand plus peroxide or peroxide alone gave little or no reaction. Fe-L + H{sub 2}O{sub 2} was superior to the Fentonmore »
- Authors:
- Publication Date:
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 245371
- Resource Type:
- Journal Article
- Journal Name:
- Journal of Environmental Quality
- Additional Journal Information:
- Journal Volume: 23; Journal Issue: 2; Other Information: PBD: Mar-Apr 1994
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 54 ENVIRONMENTAL SCIENCES; IRON COMPLEXES; CATALYTIC EFFECTS; HERBICIDES; DECOMPOSITION; SOILS; REMEDIAL ACTION; CATALYSTS; GALLIC ACID; HYDROGEN PEROXIDE; HEIDA; NTA; OXIDATION; SORPTION; DECHLORINATION
Citation Formats
Pignatello, J J, and Baehr, K. Ferric complexes as catalysts for {open_quotes}Fenton{close_quotes} degradation of 2,4-D and metolachlor in soil. United States: N. p., 1994.
Web. doi:10.2134/jeq1994.00472425002300020023x.
Pignatello, J J, & Baehr, K. Ferric complexes as catalysts for {open_quotes}Fenton{close_quotes} degradation of 2,4-D and metolachlor in soil. United States. https://doi.org/10.2134/jeq1994.00472425002300020023x
Pignatello, J J, and Baehr, K. 1994.
"Ferric complexes as catalysts for {open_quotes}Fenton{close_quotes} degradation of 2,4-D and metolachlor in soil". United States. https://doi.org/10.2134/jeq1994.00472425002300020023x.
@article{osti_245371,
title = {Ferric complexes as catalysts for {open_quotes}Fenton{close_quotes} degradation of 2,4-D and metolachlor in soil},
author = {Pignatello, J J and Baehr, K},
abstractNote = {Fenton-type reactions of hydrogen peroxide with Fe compounds generate bydroxyl radical (OH{center_dot}) or other reactive species and are potentially useful for degrading organic contaminants in soil. The use of simple Fe salts is limited, however. This study investigated certain pH 6-soluble Fe(III) complexes (Fe-L, where L is an organic tigand) as catalysts for degradation of herbicides 2,4-dichlorophenoxyacetic acid (2,4-D) and metolachlor (2-chloro-N-[2-ethyl 6-methylphenyl]-N-[2-methoxy-l-methylethyl]acetamide). Reactions were carried out in 1:1 aqueous suspensions of a topsoil (15.7 g kg{sup -1} organic C) at the natural pH of 5.7 with herbicides at concentrations representative of a spill (2-3 g kg{sup -1} about 0.01 mol kg{sup -1}). The two herbicides had contrasting sorption behavior in that 2,4-D was mostly in solution, whereas metotachlor was mostly sorbed. The best results were obtained using Fe-nitrilotriscetate (NTA) or Fe-hydroxyethyleniminodiacetate (HEIDA) at 0.01 mol kg-{sup -1} and [H{sub 2}O{sub 2}]{ge} 0.5 mol kg{sup -1}. The gallic acid complex was less effective. In 3 h,{sup 14}C-labeled 2,4-D was quantitatively dechlorinated and partially (15-30%) converted to {sup 14}CO{sub 2}: metolachlor was 93% transformed and 29% dechlorinated. Controls using free ligand plus peroxide or peroxide alone gave little or no reaction. Fe-L + H{sub 2}O{sub 2} was superior to the Fenton reagent itself (Fe{sup 2+} + H{sub 2}O{sub 2}). The results of this study demonstrate that relatively mild chemical oxidation can be effective for remediation of certain contaminants in soil 23 refs., 2 figs., 6 tabs.},
doi = {10.2134/jeq1994.00472425002300020023x},
url = {https://www.osti.gov/biblio/245371},
journal = {Journal of Environmental Quality},
number = 2,
volume = 23,
place = {United States},
year = {Tue Mar 01 00:00:00 EST 1994},
month = {Tue Mar 01 00:00:00 EST 1994}
}