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Schacherl B, Joseph C, Beck A, Lavrova P, Schnurr A, Dardenne K, Geyer F, Cherkezova-Zheleva Z, Göttlicher J, Geckeis H, Vitova T. Np(V) Retention at the Illite du Puy Surface. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:11185-11194. [PMID: 37460108 PMCID: PMC10399294 DOI: 10.1021/acs.est.2c09356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
In this study, Np(V) retention on Illite du Puy (IdP) was investigated since it is essential for understanding the migration behavior of Np in argillaceous environments. The presence of structural Fe(III) and Fe(II) in IdP was confirmed by Fe K-edge X-ray absorption near-edge structure (XANES) and 57Fe Mössbauer spectroscopy. In batch sorption experiments, a higher Np sorption affinity to IdP was found than to Wyoming smectite or iron-free synthetic montmorillonite. An increase of the relative Np(IV) ratio sorbed onto IdP with decreasing pH was observed by solvent extraction (up to (24 ± 2)% at pH 5, c0(Np) = 10-6 mol/L). Furthermore, up to (33 ± 5)% Np(IV) could be detected in IdP diffusion samples at pH 5. Respective Np M5-edge high-energy resolution (HR-) XANES spectra suggested the presence of Np(IV/V) mixtures and weakened axial bond covalency of the NpO2+ species sorbed onto IdP. Np L3-edge extended X-ray absorption fine structure (EXAFS) analysis showed that significant fractions of Np were coordinated to Fe─O entities at pH 9. This highlights the potential role of Fe(II/III) clay edge sites as a strong Np(V) surface complex partner and points to the partial reduction of sorbed Np(V) to Np(IV) via structural Fe(II).
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Affiliation(s)
- Bianca Schacherl
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, D-76021 Karlsruhe, Germany
| | - Claudia Joseph
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, D-76021 Karlsruhe, Germany
| | - Aaron Beck
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, D-76021 Karlsruhe, Germany
| | - Polina Lavrova
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, D-76021 Karlsruhe, Germany
| | - Andreas Schnurr
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, D-76021 Karlsruhe, Germany
| | - Kathy Dardenne
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, D-76021 Karlsruhe, Germany
| | - Frank Geyer
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, D-76021 Karlsruhe, Germany
| | - Zara Cherkezova-Zheleva
- Institute of Catalysis, Bulgarian Academy of Sciences, "Acad. G. Bonchev" Str., Bl.11, 1113 Sofia, Bulgaria
| | - Jörg Göttlicher
- Karlsruhe Institute of Technology (KIT), Institute for Photon Science and Synchrotron Radiation (IPS), P.O. Box 3640, D-76021 Karlsruhe, Germany
| | - Horst Geckeis
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, D-76021 Karlsruhe, Germany
| | - Tonya Vitova
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, D-76021 Karlsruhe, Germany
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Safonov A, Lavrinovich E, Emel'yanov A, Boldyrev K, Kuryakov V, Rodygina N, Zakharova E, Novikov A. Risk of colloidal and pseudo-colloidal transport of actinides in nitrate contaminated groundwater near a radioactive waste repository after bioremediation. Sci Rep 2022; 12:4557. [PMID: 35296759 PMCID: PMC8927300 DOI: 10.1038/s41598-022-08593-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Accepted: 03/04/2022] [Indexed: 11/28/2022] Open
Abstract
The possible role of biogeochemical processes in the transport of colloidal and pseudo-colloidal U, Np, and Pu during bioremediation of radionuclide- and nitrate-contaminated groundwater was investigated. In two laboratory experiments with water samples taken from contaminated aquifers before and post bioremediation, we found that microbial processes could cause clayed, ferruginous, and actinide colloids to coagulate. The main mechanisms are biogenic insoluble ferrous iron species formations (goethite, pyrrhotite, siderite, troilite, and ferrihydrite), the aggregation of clay particles by microbial metabolites, and the immobilization of actinides in the bacterial cells, large polymers, and iron and clayed sediments. This process decreases the risk of colloidal and pseudo-colloidal transport of actinides.
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Affiliation(s)
- Alexey Safonov
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31, Leninsky prospect, 199071, Moscow, Russia.
| | - Elena Lavrinovich
- Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Kosygin str. 19, 119991, Moscow, Russia
| | - Alexander Emel'yanov
- Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Kosygin str. 19, 119991, Moscow, Russia
| | - Kirill Boldyrev
- Nuclear Safety Institute of the Russian Academy of Sciences, 52, Bolshaya Tulskaya, 115191б, Moscow, Russia
| | - Vladimir Kuryakov
- Oil and Gas Research Institute of the Russian Academy of Sciences, Gubkina str. 3, 119333, Moscow, Russia
| | - Natalia Rodygina
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31, Leninsky prospect, 199071, Moscow, Russia
| | - Elena Zakharova
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31, Leninsky prospect, 199071, Moscow, Russia
| | - Alexander Novikov
- Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Kosygin str. 19, 119991, Moscow, Russia
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Schacherl B, Joseph C, Lavrova P, Beck A, Reitz C, Prüssmann T, Fellhauer D, Lee JY, Dardenne K, Rothe J, Geckeis H, Vitova T. Paving the way for examination of coupled redox/solid-liquid interface reactions: 1 ppm Np adsorbed on clay studied by Np M5-edge HR-XANES spectroscopy. Anal Chim Acta 2022; 1202:339636. [DOI: 10.1016/j.aca.2022.339636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 02/06/2022] [Accepted: 02/17/2022] [Indexed: 11/01/2022]
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Tarrahi R, Mahjouri S, Khataee A. A review on in vivo and in vitro nanotoxicological studies in plants: A headlight for future targets. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 208:111697. [PMID: 33396028 DOI: 10.1016/j.ecoenv.2020.111697] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 11/01/2020] [Accepted: 11/18/2020] [Indexed: 06/12/2023]
Abstract
Owing to the unique properties and useful applications in numerous fields, nanomaterials (NMs) received a great attention. The mass production of NMs has raised major concern for the environment. Recently, some altered growth patterns in plants have been reported due to the plant-NMs interactions. However, for NMs safe applications in agriculture and medicine, a comprehensive understanding of bio-nano interactions is crucial. The main goal of this review article is to summarize the results of the toxicological studies that have shown the in vitro and in vivo interactions of NMs with plants. The toxicity mechanisms are briefly discussed in plants as the defense mechanism works to overcome the stress caused by NMs implications. Indeed, the impact of NMs on plants varies significantly with many factors including physicochemical properties of NMs, culture media, and plant species. To investigate the impacts, dose metrics is an important analysis for assaying toxicity and is discussed in the present article to broadly open up different aspects of nanotoxicological investigations. To access reliable quantification and measurement in laboratories, standardized methodologies are crucial for precise dose delivery of NMs to plants during exposure. Altogether, the information is significant to researchers to describe restrictions and future perspectives.
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Affiliation(s)
- Roshanak Tarrahi
- Health Promotion Research Center, Iran University of Medical Sciences, 14496-14535 Tehran, Iran
| | - Sepideh Mahjouri
- Department of Biological Sciences, Faculty of Basic Sciences, Higher Education Institute of Rab-Rashid, Tabriz, Iran
| | - Alireza Khataee
- Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, 51666-16471 Tabriz, Iran; Рeoples' Friendship University of Russia (RUDN University), 6 Miklukho-Maklaya Street, Moscow 117198, Russian Federation.
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Baumer T, Hixon AE. Kinetics of neptunium sorption and desorption in the presence of aluminum (hydr)oxide minerals: Evidence for multi-step desorption at low pH. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2019; 205-206:72-78. [PMID: 31121423 DOI: 10.1016/j.jenvrad.2019.05.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 05/02/2019] [Accepted: 05/10/2019] [Indexed: 06/09/2023]
Abstract
Kinetics analyses of sorption and desorption provide important insight into reaction mechanisms occurring at the mineral-water interface. They are also needed to determine when equilibrium is achieved, identify intermediate chemical species, and inform models describing neptunium mobility. Neptunium sorption to and desorption from four different aluminum (hydr)oxides - bayerite (α-Al(OH)3), gibbsite (γ-Al(OH)3), corundum (α-Al2O3), and γ-alumina (γ-Al2O3) - were investigated as a function of mineral concentration (5 - 170 m2 L-1), neptunium concentration (10-9 - 10-7 M), and pH (5.5 - 10.5). Neptunium sorption was characterized by a two-step reaction with an initial fast sorption step occurring within minutes followed by a slower equilibrium process, which was attributed to initial sorption of neptunium to a small number of strong sorption sites followed by sorption of neptunium to a larger number of weak sorption sites. The kinetics data were modeled using the linear and non-linear forms of the pseudo-first and pseudo-second order rate equations and the goodness of fit parameters were compared. Non-linear pseudo-second order rate constants described neptunium sorption to aluminum (hydr)oxides most accurately and were used to determine the reaction orders with respect to mineral concentration and [H+]. Neptunium desorption experiments demonstrated that the desorption mechanism changed as a function of pH and that the forward and reverse reactions were not equivalent. At pH ≥ 7.5, desorption reached steady-state within an hour and was accurately described by the non-linear pseudo-second order rate equations. A desorption plateau was observed at pH 5.5 that could not be described by either pseudo-first or -second order kinetics, suggesting the possibility of a multi-step desorption reaction. The comparatively slow desorption kinetics observed here suggests that sorbed neptunium could be slowly released back into the aqueous phase and act as a continuous source of contamination to the environment.
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Affiliation(s)
- Teresa Baumer
- Department of Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Amy E Hixon
- Department of Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, IN, 46556, USA.
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Petrov VG, Fellhauer D, Gaona X, Dardenne K, Rothe J, Kalmykov SN, Altmaier M. Solubility and hydrolysis of Np(V) in dilute to concentrated alkaline NaCl solutions: formation of Na–Np(V)–OH solid phases at 22 °C. RADIOCHIM ACTA 2016. [DOI: 10.1515/ract-2016-2614] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The solubility of Np(V) was investigated at T=22±2°C in alkaline NaCl solutions of different ionic strength (0.1–5.0 M). The solid phases controlling the solubility at different –log10 mH+(pHm) and NaCl concentration were characterized by XRD, quantitative chemical analysis, SEM–EDS and XAFS (both XANES and EXAFS). Aqueous phases in equilibrium with Np(V) solids were investigated for selected samples within 8.9≤pHm≤10.3 by UV-vis/NIR absorption spectroscopy. In 0.1 M NaCl, the experimental solubility of the initial greenish NpO2OH(am) solid phase is in good agreement with previous results obtained in NaClO4 solutions, and is consistent with model calculations for fresh NpO2OH(am) using the thermodynamic data selection in NEA–TDB. Below pHm~11.5 and for all NaCl concentrations studied, Np concentration in equilibrium with the solid phase remained constant during the timeframe of this study (~2 years). This observation is in contrast to the aging of the initial NpO2OH(am) into a more crystalline modification with the same stoichiometry, NpO2OH(am, aged), as reported in previous studies for concentrated NaClO4 and NaCl. Instead, the greenish NpO2OH(am) transforms into a white solid phase in those systems with [NaCl]≥1.0 M and pHm≥11.5, and into two different pinkish phases above pHm~13.2. The solid phase transformation is accompanied by a drop in Np solubility of 0.5–2 log10-units (depending upon NaCl concentration). XANES analyses of green, white and pink phases confirm the predominance of Np(V) in all cases. Quantitative chemical analysis shows the incorporation of Na+ in the original NpO2OH(am) material, with Na:Np≤0.3 for the greenish solids and 0.8≤Na:Np≤1.6 for the white and pinkish phases. XRD data confirms the amorphous character of the greenish phase, whereas white and pink solids show well-defined but discrepant XRD patterns. Furthermore, the XRD pattern collected for one of the pink solid phases match the data recently reported for NaNpO2(OH)2(cr). UV-vis/NIR spectra collected in 0.1–5.0 M NaCl solutions show the predominance of NpO2
+ (≥80%) at pHm≤10.3. This observation is consistent with the Np(V) hydrolysis scheme currently selected in the NEA–TDB. This work provides sound evidences on the formation of ternary Na–Np(V)–OH solid phases in Na-rich hyperalkaline solutions and ambient temperature conditions. Given the unexpectedly high complexity of the system, further experimental efforts dedicated to assess the thermodynamic properties of these solid phases are needed, especially in view of their likely relevance as solubility controlling Np(V) solid phases in Na-rich systems such as saline and cement-based environments in the context of the safety assessment for nuclear waste disposal.
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Affiliation(s)
- Vladimir G. Petrov
- Lomonosov Moscow State University, Department of Chemistry, 119991, Leninskie gory, 1 bld. 3, Moscow, Russia
| | - David Fellhauer
- Karlsruhe Institute of Technology, Institute for Nuclear Waste Disposal, P.O. Box 3640, 76021 Karlsruhe, Germany
| | - Xavier Gaona
- Karlsruhe Institute of Technology, Institute for Nuclear Waste Disposal, P.O. Box 3640, 76021 Karlsruhe, Germany
| | - Kathy Dardenne
- Karlsruhe Institute of Technology, Institute for Nuclear Waste Disposal, P.O. Box 3640, 76021 Karlsruhe, Germany
| | - Jörg Rothe
- Karlsruhe Institute of Technology, Institute for Nuclear Waste Disposal, P.O. Box 3640, 76021 Karlsruhe, Germany
| | - Stepan N. Kalmykov
- Lomonosov Moscow State University, Department of Chemistry, 119991, Leninskie gory, 1 bld. 3, Moscow, Russia
- NRC Kurchatov Institute, 123182, Akademika Kurchatova pl. 1, Moscow, Russia
| | - Marcus Altmaier
- Karlsruhe Institute of Technology, Institute for Nuclear Waste Disposal, P.O. Box 3640, 76021 Karlsruhe, Germany
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Shi WQ, Yuan LY, Wang CZ, Wang L, Mei L, Xiao CL, Zhang L, Li ZJ, Zhao YL, Chai ZF. Exploring actinide materials through synchrotron radiation techniques. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2014; 26:7807-7848. [PMID: 25169914 DOI: 10.1002/adma.201304323] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 04/24/2014] [Indexed: 06/03/2023]
Abstract
Synchrotron radiation (SR) based techniques have been utilized with increasing frequency in the past decade to explore the brilliant and challenging sciences of actinide-based materials. This trend is partially driven by the basic needs for multi-scale actinide speciation and bonding information and also the realistic needs for nuclear energy research. In this review, recent research progresses on actinide related materials by means of various SR techniques were selectively highlighted and summarized, with the emphasis on X-ray absorption spectroscopy, X-ray diffraction and scattering spectroscopy, which are powerful tools to characterize actinide materials. In addition, advanced SR techniques for exploring future advanced nuclear fuel cycles dealing with actinides are illustrated as well.
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Affiliation(s)
- Wei-Qun Shi
- Key Laboratory of Nuclear Radiation and Nuclear Energy Technology, Institute of High Enegy Physics, Chinese Academy of Sciences, Beijing, 100049, China
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Natrajan LS, Swinburne AN, Andrews MB, Randall S, Heath SL. Redox and environmentally relevant aspects of actinide(IV) coordination chemistry. Coord Chem Rev 2014. [DOI: 10.1016/j.ccr.2013.12.021] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Zänker H, Hennig C. Colloid-borne forms of tetravalent actinides: a brief review. JOURNAL OF CONTAMINANT HYDROLOGY 2014; 157:87-105. [PMID: 24365396 DOI: 10.1016/j.jconhyd.2013.11.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 11/08/2013] [Accepted: 11/26/2013] [Indexed: 06/03/2023]
Abstract
Tetravalent actinides, An(IV), are usually assumed to be little mobile in near-neutral environmental waters because of their low solubility. However, there are certain geochemical scenarios during which mobilization of An(IV) in a colloid-borne (waterborne) form cannot be ruled out. A compilation of colloid-borne forms of tetravalent actinides described so far for laboratory experiments together with several examples of An(IV) colloids observed in field experiments and real-world scenarios are given. They are intended to be a knowledge base and a tool for those who have to interpret actinide behavior under environmental conditions. Synthetic colloids containing structural An(IV) and synthetic colloids carrying adsorbed An(IV) are considered. Their behavior is compared with the behavior of An(IV) colloids observed after the intentional or unintentional release of actinides into the environment. A list of knowledge gaps as to the behavior of An(IV) colloids is provided and items which need further research are highlighted.
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Affiliation(s)
- Harald Zänker
- Institute of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf, P.O. Box 51 01 19, D-01314 Dresden, Germany.
| | - Christoph Hennig
- Institute of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf, P.O. Box 51 01 19, D-01314 Dresden, Germany
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Affiliation(s)
- Kate Maher
- Department of Geological & Environmental Sciences, Stanford University, Stanford, California 94305-2115, United States
| | | | - Gordon E. Brown
- Department of Geological & Environmental Sciences, Stanford University, Stanford, California 94305-2115, United States
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Kirsch R, Fellhauer D, Altmaier M, Neck V, Rossberg A, Fanghänel T, Charlet L, Scheinost AC. Oxidation state and local structure of plutonium reacted with magnetite, mackinawite, and chukanovite. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:7267-74. [PMID: 21755920 DOI: 10.1021/es200645a] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Due to their redox reactivity, surface sorption characteristics, and ubiquity as corrosion products or as minerals in natural sediments, iron(II)-bearing minerals control to a large extent the environmental fate of actinides. Pu-L(III)-edge XANES and EXAFS spectra were used to investigate reaction products of aqueous (242)Pu(III) and (242)Pu(V) reacted with magnetite, mackinawite, and chukanovite under anoxic conditions. As Pu concentrations in the liquid phase were rapidly below detection limit, oxidation state and local structure of Pu were determined for Pu associated with the solid mineral phase. Pu(V) was reduced in the presence of all three minerals. A newly identified, highly specific Pu(III)-sorption complex formed with magnetite. Solid PuO(2) phases formed in the presence of mackinawite and chukanovite; in the case of chukanovite, up to one-third of plutonium was also present as Pu(III). This highlights the necessity to consider, under reducing anoxic conditions, Pu(III) species in addition to tetravalent PuO(2) for environmental risk assessment. Our results also demonstrate the necessity to support thermodynamic calculations with spectroscopic data.
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Affiliation(s)
- Regina Kirsch
- Institut für Radiochemie, Helmholtz Zentrum Dresden Rossendorf, Postfach 510119, 01314 Dresden, Germany.
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Powell BA, Dai Z, Zavarin M, Zhao P, Kersting AB. Stabilization of plutonium nano-colloids by epitaxial distortion on mineral surfaces. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:2698-2703. [PMID: 21446768 DOI: 10.1021/es1033487] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The subsurface migration of Pu may be enhanced by the presence of colloidal forms of Pu. Therefore, complete evaluation of the risk posed by subsurface Pu contamination needs to include a detailed physical/chemical understanding of Pu colloid formation and interactions of Pu colloids with environmentally relevant solid phases. Transmission electron microscopy (TEM) was used to characterize Pu nanocolloids and interactions of Pu nanocolloids with goethite and quartz. We report that intrinsic Pu nanocolloids generated in the absence of goethite or quartz were 2-5 nm in diameter, and both electron diffraction analysis and HRTEM confirm the expected Fm3m space group with the fcc, PuO2 structure. Plutonium nanocolloids formed on goethite have undergone a lattice distortion relative to the ideal fluorite-type structure, fcc, PuO2, resulting in the formation of a bcc, Pu4O7 structure. This structural distortion results from an epitaxial growth of the plutonium colloid on goethite, leading to stronger binding of plutonium to goethite compared with other minerals such as quartz, where the distortion was not observed. This finding provides new insight for understanding how molecular-scale behavior at the mineral-water interface may facilitate transport of plutonium at the field scale.
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Affiliation(s)
- Brian A Powell
- Environmental Engineering and Earth Sciences, Clemson University, 342 Computer Court, Anderson, South Carolina 29625, United States.
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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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Evolution of actinide partitioning with colloidal matter collected at PA “Mayak” site as studied by sequential extraction. J Radioanal Nucl Chem 2009. [DOI: 10.1007/s10967-008-7397-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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