Tits, Jan; Walther, Clemens; Stumpf, Thorsten; Mace, Nathalie; Wieland, Erich: A luminescence line-narrowing spectroscopic study of the uranium(VI) interaction with cementitious materials and titanium dioxide. In: Dalton Transactions 44 (2015), Nr. 3, S. 966-976. DOI:
http://dx.doi.org/10.1039/c4dt02172j
Zusammenfassung: |
Non-selective luminescence spectroscopy and luminescence line-narrowing spectroscopy were used to study the retention of UO22+ on titanium dioxide (TiO2), synthetic calcium silicate hydrate (C-S-H) phases and hardened cement paste (HCP). Non-selective luminescence spectra showed strong inhomogeneous line broadening resulting from a strongly disordered UO22+ bonding environment. This problem was largely overcome by using luminescence line-narrowing spectroscopy. This technique allowed unambiguous identification of three different types of UO22+ sorbed species on C-S-H phases and HCP. Comparison with spectra of UO22+ sorbed onto TiO2 further allowed these species to be assigned to a surface complex, an incorporated species and an uranate-like surface precipitate. This information provides the basis for mechanistic models describing the UO22+ sorption onto C-S-H phases and HCP and the assessment of the mobility of this radionuclide in a deep geological repository for low and intermediate level radioactive waste (L/ILW) as this kind of waste is often solidified with cement prior to storage.
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Lizenzbestimmungen: |
CC BY 3.0 Unported - http://creativecommons.org/licenses/by/3.0/
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Publikationstyp: |
Article |
Publikationsstatus: |
publishedVersion |
Erstveröffentlichung: |
2015 |
Schlagwörter (englisch): |
laser fluorescence spectroscopy, silicate hydrate phases, uranyl ions, electronic-structure, actinyl ions, u(vi), sorption, solubility, speciation, complexes
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Fachliche Zuordnung (DDC): |
540 | Chemie
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