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Bezzina JP, Neumann J, Brendler V, Schmidt M. Combining batch experiments and spectroscopy for realistic surface complexation modelling of the sorption of americium, curium, and europium onto muscovite. WATER RESEARCH 2022; 223:119032. [PMID: 36067603 DOI: 10.1016/j.watres.2022.119032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 08/24/2022] [Accepted: 08/26/2022] [Indexed: 06/15/2023]
Abstract
For a safe enclosure of contaminants, for instance in deep geological repositories of radioactive waste, any processes retarding metal migration are of paramount importance. This study focusses on the sorption of trivalent actinides (Am, Cm) and lanthanides (Eu) to the surface of muscovite, a mica and main component of most crystalline rocks (granites, granodiorites). Batch sorption experiments quantified the retention regarding parameters like pH (varied between 3 and 9), metal concentration (from 0.5 µM Cm to 10 µM Eu), or solid-to-liquid ratio (0.13 and 5.25 g·L-1). In addition, time-resolved laser fluorescence spectroscopy (TRLFS) using the actinide Cm(III) identified two distinct inner-sphere surface species. Combining both approaches allowed the development of a robust surface complexation model and the determination of stability constants of the spectroscopically identified species of (S-OH)2M3+ (logKo -8.89), (S-O)2M+ (logKo -4.11), and (S-O)2MOH (logKo -10.6), with all values extrapolated to infinite dilution. The inclusion of these stability constants into thermodynamic databases will improve the prognostic accuracy of lanthanide and actinide transport through groundwater channels in soils and crystalline rock systems.
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Affiliation(s)
- James P Bezzina
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, Dresden 01328, Germany
| | - Julia Neumann
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, Dresden 01328, Germany
| | - Vinzenz Brendler
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, Dresden 01328, Germany
| | - Moritz Schmidt
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Bautzner Landstraße 400, Dresden 01328, Germany.
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2
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Demnitz M, Molodtsov K, Schymura S, Schierz A, Müller K, Jankovsky F, Havlova V, Stumpf T, Schmidt M. Effects of surface roughness and mineralogy on the sorption of Cm(III) on crystalline rock. JOURNAL OF HAZARDOUS MATERIALS 2022; 423:127006. [PMID: 34481396 DOI: 10.1016/j.jhazmat.2021.127006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 08/10/2021] [Accepted: 08/19/2021] [Indexed: 06/13/2023]
Abstract
Crystalline rock is one of the host rocks considered for a future deep geological repository for highly active radiotoxic nuclear waste. The safety assessment requires reliable information on the retention behavior of minor actinides. In this work, we applied various spatially resolved techniques to investigate the sorption of Curium onto crystalline rock (granite, gneiss) thin sections from Eibenstock, Germany and Bukov, Czech Republic. We combined Raman-microscopy, calibrated autoradiography and µTRLFS (micro-focus time-resolved fluorescence spectroscopy) with vertical scanning interferometry to study in situ the impact of mineralogy and surface roughness on Cm(III) uptake and molecular speciation on the surface. Heterogeneous sorption of Cm(III) on the surface depends primarily on the mineralogy. However, for the same mineral class sorption uptake and strength of Cm(III) increases with growing surface roughness around surface holes or grain boundaries. When competitive sorption between multiple mineral phases occurs, surface roughness becomes the major retention parameter on low sorption uptake minerals. In high surface roughness areas primarily Cm(III) inner-sphere sorption complexation and surface incorporation are prominent and in selected sites formation of stable Cm(III) ternary complexes is observed. Our molecular findings confirm that predictive radionuclide modelling should implement surface roughness as a key parameter in simulations.
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Affiliation(s)
- M Demnitz
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany
| | - K Molodtsov
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany
| | - S Schymura
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Resource Ecology, Research Site Leipzig, Permoserstr. 15, 04318 Leipzig, Germany
| | - A Schierz
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany
| | - K Müller
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany
| | - F Jankovsky
- ÚJV Rez, a.s., Hlavni 130, Rez, 250 68 Husinec, Czech Republic
| | - V Havlova
- ÚJV Rez, a.s., Hlavni 130, Rez, 250 68 Husinec, Czech Republic
| | - T Stumpf
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany
| | - M Schmidt
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden, Germany.
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Sorption of Eu(III) on Eibenstock granite studied by µTRLFS: A novel spatially-resolved luminescence-spectroscopic technique. Sci Rep 2019; 9:6287. [PMID: 31000739 PMCID: PMC6472502 DOI: 10.1038/s41598-019-42664-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 04/04/2019] [Indexed: 11/08/2022] Open
Abstract
In this study a novel technique, micro-focus time-resolved laser-induced luminescence spectroscopy (µTRLFS) is presented to investigate heterogeneous systems like granite (mainly consisting of quartz, feldspar, and mica), regarding their sorption behavior. µTRLFS is a spatially-resolved upgrade of conventional TRLFS, which allows point-by-point analysis of single minerals by reducing the beam size of the analytic laser beam to below the size of mineral grains. This provides visualization of sorption capacity as well as speciation of a luminescent probe, here Eu3+. A thin-section of granitic rock from Eibenstock, Saxony, Germany was analyzed regarding its mineralogy with microprobe X-ray fluorescence (µXRF) and electron probe microanalysis (EPMA). Afterwards, it was reacted with 5.0 × 10−5 mol/L Eu3+ at pH 8.0 and uptake was quantified by autoradiography. Finally, the µTRLFS studies were conducted. The results clearly show that the materials interact differently with Eu3+, and often even on one mineral grain different speciations can be found. Alkali-feldspar shows very high uptake, with an inhomogeneous distribution, and intermediate sorption strength. On quartz uptake is almost 10-fold lower, while the complexation strength is higher than on feldspar. This may be indicative of adsorption only at surface defect sites, in accordance with low hydration of the observed species.
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Fernandes MM, Scheinost AC, Baeyens B. Sorption of trivalent lanthanides and actinides onto montmorillonite: Macroscopic, thermodynamic and structural evidence for ternary hydroxo and carbonato surface complexes on multiple sorption sites. WATER RESEARCH 2016; 99:74-82. [PMID: 27140904 DOI: 10.1016/j.watres.2016.04.046] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 04/05/2016] [Accepted: 04/17/2016] [Indexed: 06/05/2023]
Abstract
The credibility of long-term safety assessments of radioactive waste repositories may be greatly enhanced by a molecular level understanding of the sorption processes onto individual minerals present in the near- and far-fields. In this study we couple macroscopic sorption experiments to surface complexation modelling and spectroscopic investigations, including extended X-ray absorption fine structure (EXAFS) and time-resolved laser fluorescence spectroscopies (TRLFS), to elucidate the uptake mechanism of trivalent lanthanides and actinides (Ln/An(III)) by montmorillonite in the absence and presence of dissolved carbonate. Based on the experimental sorption isotherms for the carbonate-free system, the previously developed 2 site protolysis non electrostatic surface complexation and cation exchange (2SPNE SC/CE) model needed to be complemented with an additional surface complexation reaction onto weak sites. The fitting of sorption isotherms in the presence of carbonate required refinement of the previously published model by reducing the strong site capacity and by adding the formation of Ln/An(III)-carbonato complexes both on strong and weak sites. EXAFS spectra of selected Am samples and TRLFS spectra of selected Cm samples corroborate the model assumptions by showing the existence of different surface complexation sites and evidencing the formation of Ln/An(III) carbonate surface complexes. In the absence of carbonate and at low loadings, Ln/An(III) form strong inner-sphere complexes through binding to three Al(O,OH)6 octahedra, most likely by occupying vacant sites in the octahedral layers of montmorillonite, which are exposed on {010} and {110} edge faces. At higher loadings, Ln/An(III) binds to only one Al octahedron, forming a weaker, edge-sharing surface complex. In the presence of carbonate, we identified a ternary mono- or dicarbonato Ln/An(III) complex binding directly to one Al(O,OH)6 octahedron, revealing that type-A ternary complexes form with the one or two carbonate groups pointing away from the surface into the solution phase. Within the spectroscopically observable concentration range these complexes could only be identified on the weak sites, in line with the small strong site capacity suggested by the refined sorption model. When the solubility of carbonates was exceeded, formation of an Am carbonate hydroxide could be identified. The excellent agreement between the thermodynamic model parameters obtained by fitting the macroscopic data, and the spectroscopically identified mechanisms, demonstrates the mature state of the 2SPNE SC/CE model for predicting and quantifying the retention of Ln/An(III) elements by montmorillonite-rich clay rocks.
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Affiliation(s)
- M Marques Fernandes
- Paul Scherrer Institute, Laboratory for Waste Management, 5232 Villigen PSI, Switzerland.
| | - A C Scheinost
- Helmholtz Zentrum Dresden Rossendorf e.V. (HZDR), Institute of Resource Ecology, 01314 Dresden, Germany; The Rossendorf Beamline at ESRF, 38043 Grenoble, France
| | - B Baeyens
- Paul Scherrer Institute, Laboratory for Waste Management, 5232 Villigen PSI, Switzerland
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Verma PK, Mohapatra PK. Effect of different complexing ligands on europium uptake from aqueous phase by kaolinite: batch sorption and fluorescence studies. RSC Adv 2016. [DOI: 10.1039/c6ra17984c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The fluorescence studies suggested that the Eu(iii) sorbs as Eu(iii)–oxalate complex (binary system) onto kaolinite surface in the ternary system of Eu(iii), oxalic acid and kaolinite at circumneutral pH conditions.
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6
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Macroscopic and spectroscopic investigations on Eu(III) and Cm(III) sorption onto bayerite (β-Al(OH)3) and corundum (α-Al2O3). J Colloid Interface Sci 2016; 461:215-224. [DOI: 10.1016/j.jcis.2015.09.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 08/04/2015] [Accepted: 09/08/2015] [Indexed: 11/19/2022]
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7
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Tits J, Walther C, Stumpf T, Macé N, Wieland E. A luminescence line-narrowing spectroscopic study of the uranium(vi) interaction with cementitious materials and titanium dioxide. Dalton Trans 2015; 44:966-76. [DOI: 10.1039/c4dt02172j] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Luminescence line-narrowing spectroscopy has been applied to identify the mechanisms controlling the uranium retention by titanium dioxide and cement minerals.
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Affiliation(s)
- Jan Tits
- Laboratory for Waste Management
- Paul Scherrer Institute
- CH-5232 Villigen PSI
- Switzerland
| | - Clemens Walther
- Institute for Nuclear Waste Disposal
- Karlsruhe Institute of Technology
- D-76344 Eggenstein-Leopoldshafen
- Germany
| | - Thorsten Stumpf
- Institute for Nuclear Waste Disposal
- Karlsruhe Institute of Technology
- D-76344 Eggenstein-Leopoldshafen
- Germany
| | - Nathalie Macé
- Laboratory for Waste Management
- Paul Scherrer Institute
- CH-5232 Villigen PSI
- Switzerland
| | - Erich Wieland
- Laboratory for Waste Management
- Paul Scherrer Institute
- CH-5232 Villigen PSI
- Switzerland
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9
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Moreau P, Colette-Maatouk S, Gareil P, Reiller PE. Modelling of the adsorption of phenolic acids onto α,γ–alumina particles. Colloids Surf A Physicochem Eng Asp 2013. [DOI: 10.1016/j.colsurfa.2013.02.035] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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10
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Geckeis H, Lützenkirchen J, Polly R, Rabung T, Schmidt M. Mineral–Water Interface Reactions of Actinides. Chem Rev 2013; 113:1016-62. [DOI: 10.1021/cr300370h] [Citation(s) in RCA: 223] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Horst Geckeis
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal
(INE), Karlsruhe, P.O.Box 3640, D-76021 Karlsruhe, Germany
| | - Johannes Lützenkirchen
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal
(INE), Karlsruhe, P.O.Box 3640, D-76021 Karlsruhe, Germany
| | - Robert Polly
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal
(INE), Karlsruhe, P.O.Box 3640, D-76021 Karlsruhe, Germany
| | - Thomas Rabung
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal
(INE), Karlsruhe, P.O.Box 3640, D-76021 Karlsruhe, Germany
| | - Moritz Schmidt
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal
(INE), Karlsruhe, P.O.Box 3640, D-76021 Karlsruhe, Germany
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11
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Schott J, Acker M, Barkleit A, Brendler V, Taut S, Bernhard G. The influence of temperature and small organic ligands on the sorption of Eu(III) on Opalinus Clay. RADIOCHIM ACTA 2012. [DOI: 10.1524/ract.2012.1921] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
The influence of temperature up to 50 ºC and small organic ligands (citrate, tartrate) on the sorption of Eu(III) on the natural clay rock Opalinus Clay (OPA) under aerobic (p
CO2
= 10−3.5 atm) synthetic OPA pore water conditions (pH 7.6, I = 0.4 mol L−1) was investigated. Batch sorption experiments and time-resolved laser-induced fluorescence spectroscopy (TRLFS) were used to study these influencing factors on the Eu(III) sorption.
Sorption isotherms and distribution coefficients R
d (15 ºC: log R
d = 4.50 ± 0.05...50 ºC: log R
d = 5.54 ± 0.06) at 2 × 10−9 mol L−1 Eu(III) as a function of the solid-to-liquid ratio (up to 3 g L−1) and temperature were determined. A significant temperature dependency of the Eu(III) sorption was observed. With rising temperature the Eu(III) sorption increases. The surface reaction is endothermic (Δ H
sorb ∼ 50 kJ mol−1). Using TRLFS, a surface species with a luminescence emission lifetime of 201 ± 9 μs was identified.
In the presence of tartrate or citrate the Eu(III) sorption decreases with increasing ligand concentration due to a complex formation of Eu(III) in solution, with citrate having a more pronounced influence on the sorption than tartrate. With the batch sorption experiments it can be shown that at a citrate concentration larger than 10−5 mol L−1 and at a tartrate concentration larger than 10−4 mol L−1 an increasing Eu(III) desorption occurs. This result is supported by TRLFS measurements, which show the correlation between the complexation of Eu(III) by citrate or tartrate in solution and the Eu(III) desorption process. Possible Eu(III) citrate or Eu(III) tartrate surface species on OPA could not be detected using TRLFS.
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Affiliation(s)
| | - M. Acker
- Dresden University of Technology, Central Radionuclide Laboratory, Dresden, Deutschland
| | - A. Barkleit
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiochemistry, Dresden, Deutschland
| | - V. Brendler
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Radiochemistry, Dresden, Deutschland
| | - S. Taut
- Dresden University of Technology, Central Radionuclide Laboratory, Dresden, Deutschland
| | - G. Bernhard
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiochemistry, Dresden, Deutschland
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Collins RN, Saito T, Aoyagi N, Payne TE, Kimura T, Waite TD. Applications of time-resolved laser fluorescence spectroscopy to the environmental biogeochemistry of actinides. JOURNAL OF ENVIRONMENTAL QUALITY 2011; 40:731-741. [PMID: 21546659 DOI: 10.2134/jeq2010.0166] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Time-resolved laser fluorescence spectroscopy (TRLFS) is a useful means of identifying certain actinide species resulting from various biogeochemical processes. In general, TRLFS differentiates chemical species of a fluorescent metal ion through analysis of different excitation and emission spectra and decay lifetimes. Although this spectroscopic technique has largely been applied to the analysis of actinide and lanthanide ions having fluorescence decay lifetimes on the order of microseconds, such as UO , Cm, and Eu, continuing development of ultra-fast and cryogenic TRLFS systems offers the possibility to obtain speciation information on metal ions having room-temperature fluorescence decay lifetimes on the order of nanoseconds to picoseconds. The main advantage of TRLFS over other advanced spectroscopic techniques is the ability to determine in situ metal speciation at environmentally relevant micromolar to picomolar concentrations. In the context of environmental biogeochemistry, TRLFS has principally been applied to studies of (i) metal speciation in aqueous and solid phases and (ii) the coordination environment of metal ions sorbed to mineral and bacterial surfaces. In this review, the principles of TRLFS are described, and the literature reporting the application of this methodology to the speciation of actinides in systems of biogeochemical interest is assessed. Significant developments in TRLFS methodology and advanced data analysis are highlighted, and we outline how these developments have the potential to further our mechanistic understanding of actinide biogeochemistry.
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Affiliation(s)
- Richard N Collins
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW, Australia.
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Quantum chemical study of inner-sphere complexes of trivalent lanthanide and actinide ions on the corundum (0001) surface. RADIOCHIM ACTA 2010. [DOI: 10.1524/ract.2010.1763] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Sorption of trivalent metal ions onto mineral surfaces is of special relevance in the safety assessment of nuclear waste disposal. In the present quantum chemical study we mainly focused on understanding the interaction of trivalent metal ions (La3+, Eu3+ and Cm3+) with the corundum (0001) the surface. We studied how the structure of the inner-sphere complex at the corundum (0001) surface depends on the deprotonation of the surface and give a prediction for the most likely structure of the inner-sphere complex (bi-, tri- or tetradentate). We approached this question using a cluster model for the surface. By deprotonating the cluster we mimicked a chemical environment at pH values above the point of zero charge. In a first step, we tested the accuracy of Density Functional Theory calculations with the BP86 functional and various basis sets by comparing them with Møller-Plesset perturbation theory of second order on a small chemically similar test system. This is followed by a series of calculations on a large and realistic cluster which is an extended model for the formation of the inner-sphere complex at the corundum (0001) surface. Our calculations predict the highest stability for a species with six water molecules remaining in the first coordination sphere of the metal ions and forming an inner-sphere surface complex attached to three surface oxygen atoms. The formation of the inner-sphere complexes is even more favoured when the coordination takes place via one or two deprotonated surface oxygen atoms.
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Sorption speciation of lanthanides/actinides on minerals by TRLFS, EXAFS and DFT studies: a review. Molecules 2010; 15:8431-68. [PMID: 21085087 PMCID: PMC6259111 DOI: 10.3390/molecules15118431] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 11/09/2010] [Accepted: 11/15/2010] [Indexed: 11/17/2022] Open
Abstract
Lanthanides/actinides sorption speciation on minerals and oxides by means of time resolved laser fluorescence spectroscopy (TRLFS), extended X-ray absorption fine structure spectroscopy (EXAFS) and density functional theory (DFT) is reviewed in the field of nuclear disposal safety research. The theoretical aspects of the methods are concisely presented. Examples of recent research results of lanthanide/actinide speciation and local atomic structures using TRLFS, EXAFS and DFT are discussed. The interaction of lanthanides/actinides with oxides and minerals as well as their uptake are also of common interest in radionuclide chemistry. Especially the sorption and inclusion of radionuclides into several minerals lead to an improvement in knowledge of minor components in solids. In the solid-liquid interface, the speciation and local atomic structures of Eu(III), Cm(III), U(VI), and Np(IV/VI) in several natural and synthetic minerals and oxides are also reviewed and discussed. The review is important to understand the physicochemical behavior of lanthanides/actinides at a molecular level in the natural environment.
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Bouby M, Lützenkirchen J, Dardenne K, Preocanin T, Denecke M, Klenze R, Geckeis H. Sorption of Eu(III) onto titanium dioxide: Measurements and modeling. J Colloid Interface Sci 2010; 350:551-61. [DOI: 10.1016/j.jcis.2010.06.060] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Revised: 06/23/2010] [Accepted: 06/27/2010] [Indexed: 11/15/2022]
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