URANYL SORPTION SPECIES AT LOW COVERAGE ON AL-HYDROXIDE: TRLFS AND XAFS STUDIES
- DSpace Home
- →
- Геология России
- →
- ELibrary
- →
- View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.
dc.contributor.author | Froideval A. | |
dc.contributor.author | Del Nero M. | |
dc.contributor.author | Gaillard C. | |
dc.contributor.author | Barillon R. | |
dc.contributor.author | Rossini I. | |
dc.contributor.author | Hazemann J.L. | |
dc.date.accessioned | 2024-04-29T04:07:44Z | |
dc.date.available | 2024-04-29T04:07:44Z | |
dc.date.issued | 2006 | |
dc.identifier | https://elibrary.ru/item.asp?id=12091627 | |
dc.identifier.citation | Geochimica et Cosmochimica Acta, 2006, 70, 21, 5270-5284 | |
dc.identifier.issn | 0016-7037 | |
dc.identifier.uri | https://repository.geologyscience.ru/handle/123456789/43769 | |
dc.description.abstract | Detailed understanding of the respective roles of solution and surface parameters on the reactions at uranyl solution/Al-(hydr)oxide interfaces is crucial to model accurately the behaviour of U in nature. We report studies on the effects of the initial aqueous uranyl speciation in moderately acidic solutions, e.g. of mononuclear, polynuclear uranyl species and/or (potential) U(VI) colloids, on the sorption of U by large surface areas of amorphous Al-hydroxide. Investigations by Extended X-ray Absorption Fine Structure (EXAFS) and Time-Resolved Laser-induced Fluorescence Spectroscopy (TRLFS) reveal similar U coordination environments on Al-hydroxide for low to moderate U loadings of sorption samples obtained at pH 4-5, independently of the presence of mononuclear or polynuclear aqueous species, or of the potential instability of initial solutions favoring true U-colloids formation. EXAFS data can be interpreted in terms of a dimeric, bidentate, inner-sphere uranyl surface complex as an average of the U surface structures. TRLFS data, however, provide valuable insights into the complex U surface speciation. They indicate multiple uranyl surface species under moderately acidic conditions, as predominant mononuclear and/or dinuclear, inner-sphere surface complexes and as additional minor species having U atoms in a uranyl (hydr)oxide-like coordination environment. The additional species probably occur as surface polymers and/or as adsorbed true U colloids, depending on the aqueous U concentration level (1-100 ?M). These results are of importance because they suggest that Al-hydroxide surface characteristics strongly control uranyl surface species in moderately acidic systems. | |
dc.subject | COLLOID | |
dc.subject | FLUORESCENCE SPECTROSCOPY | |
dc.subject | SORPTION | |
dc.subject | URANIUM | |
dc.title | URANYL SORPTION SPECIES AT LOW COVERAGE ON AL-HYDROXIDE: TRLFS AND XAFS STUDIES | |
dc.type | Статья | |
dc.identifier.doi | 10.1016/j.gca.2006.08.027 |
Files in this item
This item appears in the following Collection(s)
-
ELibrary
Метаданные публикаций с сайта https://www.elibrary.ru