Chlorination of Iodide-Containing Waters in the Presence of CuO: Formation of Periodate
It has been shown previously that the disproportionation of halogen-containing oxidants (e.g., HOCl, HOBr, and ClO2) is enhanced by a CuO-catalyzed process. In this study, the transformation of iodine during chlorination in the presence of CuO was investigated. There is no significant enhancement of...
| Main Authors: | , , , |
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| Format: | Journal Article |
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American Chemical Society
2014
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| Online Access: | http://hdl.handle.net/20.500.11937/46071 |
| _version_ | 1848757458656296960 |
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| author | Liu, C. Salhi, E. Croue, Jean Von Gunten, Urs |
| author_facet | Liu, C. Salhi, E. Croue, Jean Von Gunten, Urs |
| author_sort | Liu, C. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | It has been shown previously that the disproportionation of halogen-containing oxidants (e.g., HOCl, HOBr, and ClO2) is enhanced by a CuO-catalyzed process. In this study, the transformation of iodine during chlorination in the presence of CuO was investigated. There is no significant enhancement of the disproportionation of hypoiodous acid (HOI) in the presence of CuO. Theformation rate of iodate (IO3-) in the CuO-HOCl-I- system significantly increased when compared to homogeneous solutions, which was ascribed to the activation of HOCl by CuO enhancing its reactivity toward HOI. In this reaction system, iodate formation rates increase with increasing CuO(0-0.5 g L-1) and bromide (0-2 µM) doses and with decreasing pH (9.6-6.6). Iodate does not adsorb to the CuO surfaces used in this study. Nevertheless, iodate concentrations decreased after a maximum was reached in the CuO-HOCl-I-(-Br-) systems. Similarly, the iodate concentrations decrease as a function of time in the CuO-HOCl-IO3- or CuO-HOBr-IO3-system, and the rates increase with decreasing pH (9.6-6.6) due to the enhanced reactivity of HOCl or HOBr in the presence of CuO. It could be demonstrated that iodate is oxidized to periodate by a CuO-activated hypohalous acid, which is adsorbed on the CuO surface. No periodate could be measured in filtered solutions because it was mainly adsorbed to CuO. The adsorbed periodate was identified by scanning electron microscopy plus energy dispersive spectroscopy and X-ray photoelectron spectroscopy. |
| first_indexed | 2025-11-14T09:28:25Z |
| format | Journal Article |
| id | curtin-20.500.11937-46071 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T09:28:25Z |
| publishDate | 2014 |
| publisher | American Chemical Society |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-460712017-09-13T15:05:24Z Chlorination of Iodide-Containing Waters in the Presence of CuO: Formation of Periodate Liu, C. Salhi, E. Croue, Jean Von Gunten, Urs It has been shown previously that the disproportionation of halogen-containing oxidants (e.g., HOCl, HOBr, and ClO2) is enhanced by a CuO-catalyzed process. In this study, the transformation of iodine during chlorination in the presence of CuO was investigated. There is no significant enhancement of the disproportionation of hypoiodous acid (HOI) in the presence of CuO. Theformation rate of iodate (IO3-) in the CuO-HOCl-I- system significantly increased when compared to homogeneous solutions, which was ascribed to the activation of HOCl by CuO enhancing its reactivity toward HOI. In this reaction system, iodate formation rates increase with increasing CuO(0-0.5 g L-1) and bromide (0-2 µM) doses and with decreasing pH (9.6-6.6). Iodate does not adsorb to the CuO surfaces used in this study. Nevertheless, iodate concentrations decreased after a maximum was reached in the CuO-HOCl-I-(-Br-) systems. Similarly, the iodate concentrations decrease as a function of time in the CuO-HOCl-IO3- or CuO-HOBr-IO3-system, and the rates increase with decreasing pH (9.6-6.6) due to the enhanced reactivity of HOCl or HOBr in the presence of CuO. It could be demonstrated that iodate is oxidized to periodate by a CuO-activated hypohalous acid, which is adsorbed on the CuO surface. No periodate could be measured in filtered solutions because it was mainly adsorbed to CuO. The adsorbed periodate was identified by scanning electron microscopy plus energy dispersive spectroscopy and X-ray photoelectron spectroscopy. 2014 Journal Article http://hdl.handle.net/20.500.11937/46071 10.1021/es5032079 American Chemical Society restricted |
| spellingShingle | Liu, C. Salhi, E. Croue, Jean Von Gunten, Urs Chlorination of Iodide-Containing Waters in the Presence of CuO: Formation of Periodate |
| title | Chlorination of Iodide-Containing Waters in the Presence of CuO: Formation of Periodate |
| title_full | Chlorination of Iodide-Containing Waters in the Presence of CuO: Formation of Periodate |
| title_fullStr | Chlorination of Iodide-Containing Waters in the Presence of CuO: Formation of Periodate |
| title_full_unstemmed | Chlorination of Iodide-Containing Waters in the Presence of CuO: Formation of Periodate |
| title_short | Chlorination of Iodide-Containing Waters in the Presence of CuO: Formation of Periodate |
| title_sort | chlorination of iodide-containing waters in the presence of cuo: formation of periodate |
| url | http://hdl.handle.net/20.500.11937/46071 |