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Microbial hexachlorobenzene dechlorination under three reducing conditions.

B V Chang·C J Su·S Y Yuan
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Abstract

The potential dechlorination of hexachlorobenzene (HCB) in medium by 1,2,3-trichlorobenzene (TCB)-adapted mixed culture under three reducing conditions was investigated. It was found that strongest to weakest HCB dechlorination occurred in the order of methanogenic conditions > sulfate-reducing conditions > denitrifying conditions. Under denitrifying conditions, no dechlorination was observed during the first 20 days of incubation. Biotransformation occurred in this order: HCB-->pentachlorobenzene (PCB)-->1,2,3,5-tetrachlorobenzene (TeCB)-->1,3,5-TCB + 1,2,4-TCB-->1,3-dichlorobenzene (DCB), HCB dechlorination was delayed following treatment with ferric chloride and manganese dioxide, but enhanced by the addition of lactate and pyruvate under methanogenic or sulfate-reducing conditions, the addition of acetate had no significant effect on HCB dechlorination under any of the three reducing conditions. Sequential dechlorination was observed at concentrations of 2-50 mg/L, but at a significantly slower rate at the highest concentrations.

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Biodegradation, EnvironmentalChloridesChlorobenzenesFerric CompoundsFungicides, IndustrialHexachlorobenzeneManganese CompoundsMethanobacteriumOxidesSulfur-Reducing BacteriaJournal ArticleResearch Support, Non-U.S. Gov't

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B V Chang, C J Su, S Y Yuan. 1998. Microbial hexachlorobenzene dechlorination under three reducing conditions.. https://doi.org/10.1016/s0045-6535(97)10231-4

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