Phosphate complexation model and its implications for chemical phosphorus removal
A phosphate complexation model is developed, in an attempt to understand the mechanistic basis of chemically mediated phosphate removal. The model presented here is based on geochemical reaction modeling techniques and uses known surface reactions possible on hydrous ferric oxide (HFO). The types of...
| Veröffentlicht in: | Water environment research : a research publication of the Water Environment Federation. - 1998. - 80(2008), 5 vom: 23. Mai, Seite 428-38 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , |
| Format: | Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2008
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| Zugriff auf das übergeordnete Werk: | Water environment research : a research publication of the Water Environment Federation |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Ferric Compounds ferric oxide 1K09F3G675 Phosphorus 27YLU75U4W |
| Zusammenfassung: | A phosphate complexation model is developed, in an attempt to understand the mechanistic basis of chemically mediated phosphate removal. The model presented here is based on geochemical reaction modeling techniques and uses known surface reactions possible on hydrous ferric oxide (HFO). The types of surface reactions and their reaction stoichiometry and binding energies (logK values) are taken from literature models of phosphate interactions with iron oxides. The most important modeling parameter is the proportionality of converting moles of precipitated HFO to reactive site density. For well-mixed systems and phosphate exposed to ferric chloride during HFO precipitation, there is a phosphate capacity of 1.18 phosphate ions per iron atom. In poorly mixed systems with phosphate exposed to iron after HFO formation, the capacity decreased to 25% of the well-mixed value. The same surface complexation model can describe multiple data sets, by varying only a single parameter proportional to the availability of reactive oxygen functional groups. This reflects the unavailability of reactive oxygen groups to bind phosphate. Electron microscope images and dye adsorption experiments demonstrate changes in reactive surface area with aging of HFO particles. Engineering implications of the model/mechanism are highlighted |
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| Beschreibung: | Date Completed 30.10.2008 Date Revised 19.11.2015 published: Print Citation Status MEDLINE |
| ISSN: | 1554-7531 |