Formation of polybrominated and polychlorinated ethylphenoxyethylphenols (PXEPEPs) during aqueous chlorination of 4-ethylphenol solutions in the presence of bromide ions
| Autor: | Sukeo Onodera, Tsuyoshi Kawakami, Iwaki Nishi, Tomohiro Kishi |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
Environmental Engineering
Aqueous solution Bromine Polybrominated Biphenyls Water Hypochlorite chemistry.chemical_element General Medicine Mass spectrometry Polychlorinated Biphenyls Gas Chromatography-Mass Spectrometry law.invention Solutions chemistry.chemical_compound Phenols chemistry law Bromide polycyclic compounds Chlorine Organic chemistry Flame ionization detector Gas chromatography Nuclear chemistry |
| Zdroj: | Journal of Environmental Science and Health, Part A. 44:641-647 |
| ISSN: | 1532-4117 1093-4529 |
| DOI: | 10.1080/10934520902847612 |
| Popis: | This investigation was undertaken to determine the effect of the bromide concentration on the formation of polyhalogenated ethylphenoxyethylphenols (PXEPEPs), including predioxins, during the chlorination of 4-ethylphenol in solution. An aqueous solution of 4-ethylphenol was treated with hypochlorite in the presence of various concentrations of bromide ions. The changes in the compositions of the halogenated products in hexane extracts of the chlorinated solution were analyzed by gas chromatograph (GC) and a flame ionization detector (FID) and mass spectrometry (MS). 4-ethylphenol was shown to from several halogenated compounds, including PXEPEPs, as by-products of chlorination. The number of substituted chlorine or bromine atoms ranged from 0 to 4. The formation of bromine-substituted PXEPEPs was observed in the presence of 0.1 equivalents of bromide ions per mole of 4-ethylphenol. The number of substituted bromine atoms increased with the amount of co-existing bromide ions. In the presence of more than one equivalent of bromide ions per mole of 4-ethylphenol, the number of bromine atoms substituted in the PXEPEPs increased, whereas the number of chlorine atoms substituted in the PXEPEPs decreased. GC-MS total ion chromatograms confirmed the formation of polybrominated and polychlorinated predioxins during the aqueous chlorination of 4-ethylphenol in the presence of bromide ions. However, at ten equivalents of bromide ions per mole of 4-ethylphenol, no predioxins were observed in the hexane extract obtained from the aqueous 4-ethylphenol solution after being treated with chlorine. The formation of PXEPEPs during the chlorination of 4-ethylphenol in the presence of bromide ions was also influenced by the reaction pH. |
| Databáze: | OpenAIRE |
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