Dechlorination of γ-hexachlorocyclohexane by zero-valent metallic iron

Zhiyuan Wang, Ping'an Peng, Weilin Huang

Research output: Contribution to journalArticle

48 Citations (Scopus)

Abstract

This study investigated the rates and pathways of γ-hexachlorocyclohexane (γ-HCH) dechlorination by granular zero-valent iron under different pH, iron dosage and temperature conditions. It was found that γ-HCH was rapidly reduced to benzene and chlorobenzene (CB) with benzene as the major product and that the dechlorination likely follows three steps of dichloroelimination to benzene, or two steps of dichloroeliminations and one step of dehydrohalogenation to CB. The calculated pseudo-first-order rate of γ-HCH degradation was 0.0125 min-1 at pH 6.73, 25 °C and 10 g L-1 iron dosage, corresponding to 55.5 min of half-life. It was also found that the rate of γ-HCH dechlorination increases as a function of reaction temperature and zero-valent iron dosage and decreases as a function of solution pH. The calculated activation energy is 33.5 kJ mol-1 at pH 6.73, which is much lower than that of dehydrohalogenation facilitated by hydroxyl under basic conditions. The study suggested that zero-valent iron could be used to effectively and efficiently transform γ-HCH.

Original languageEnglish (US)
Pages (from-to)992-997
Number of pages6
JournalJournal of Hazardous Materials
Volume166
Issue number2-3
DOIs
StatePublished - Jul 30 2009

Fingerprint

Lindane
Dechlorination
dechlorination
HCH
Iron
iron
Benzene
benzene
chlorobenzene
Temperature
Hydroxyl Radical
activation energy
half life
Half-Life
transform
Activation energy
temperature
Degradation
degradation
dosage

All Science Journal Classification (ASJC) codes

  • Environmental Engineering
  • Environmental Chemistry
  • Waste Management and Disposal
  • Pollution
  • Health, Toxicology and Mutagenesis

Keywords

  • Dechlorination
  • Kinetics
  • Zero-valent iron
  • γ-HCH

Cite this

Wang, Zhiyuan ; Peng, Ping'an ; Huang, Weilin. / Dechlorination of γ-hexachlorocyclohexane by zero-valent metallic iron. In: Journal of Hazardous Materials. 2009 ; Vol. 166, No. 2-3. pp. 992-997.
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Dechlorination of γ-hexachlorocyclohexane by zero-valent metallic iron. / Wang, Zhiyuan; Peng, Ping'an; Huang, Weilin.

In: Journal of Hazardous Materials, Vol. 166, No. 2-3, 30.07.2009, p. 992-997.

Research output: Contribution to journalArticle

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