Uranium(VI) and europium(III) speciation at the phosphate compounds-solution interface

Journal Article · Tue Jul 06 04:00:00 EDT 1999 · Langmuir

DOI:https://doi.org/10.1021/la981596v· OSTI ID:680101

Drot, R; Simoni, E ^[1]

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1. Univ. Paris-Sud, Orsay (France). Inst. de Physique Nucleaire

Prediction of radionuclides migration through a geosphere is of fundamental interest in order to evaluate the safety of an underground radwastes repository. The authors have studied uranyl and europium (III) ion sorption mechanisms onto three phosphate compounds: ZrP{sub 2}O{sub 7}, Zr{sub 2}O(PO{sub 4}){sub 2}, and Th{sub 4}(PO{sub 4}){sub 4}P{sub 2}O{sub 7}. A spectroscopic investigation which has been previously reported has allowed one to determine all species involved in the sorption processes under study. This paper presents the modeling of experimental retention data using FITEQLv3.2 code (constant capacitance model). All sorption isotherms were successfully simulated with respect to the structural constraints. The authors have shown that uranyl sorption onto the solids under study is less influenced by electrostatic interactions between aqueous species and charged on the surface than is that for europium(III) ion. Because many experimental constraints, obtained from independent spectroscopic techniques, have been taken into account for the fitting procedure, the sorption constant values can be determined accurately.

• OSTI ID: 680101
• Journal Information: Langmuir, Journal Name: Langmuir Journal Issue: 14 Vol. 15; ISSN LANGD5; ISSN 0743-7463
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
54 ENVIRONMENTAL SCIENCES
EUROPIUM COMPOUNDS
MATHEMATICAL MODELS
RADIOACTIVE WASTE DISPOSAL
RADIONUCLIDE MIGRATION
SORPTION
SORPTIVE PROPERTIES
THORIUM PHOSPHATES
URANYL COMPOUNDS
ZIRCONIUM PHOSPHATES