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Neumann J, Carr AJ, Lessing J, Soderholm L, Catalano JG, Fenter P, Lee SS. Unraveling pH-Dependent Changes in Adsorption Structure of Uranyl on Alumina (012). J Phys Chem Lett 2024; 15:3493-3501. [PMID: 38517335 DOI: 10.1021/acs.jpclett.4c00498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2024]
Abstract
Mitigating uranium transport in groundwater is imperative for ensuring access to clean water across the globe. Here, in situ resonant anomalous X-ray reflectivity is used to investigate the adsorption of uranyl on alumina (012) in acidic aqueous solutions, representing typical UVI concentrations of contaminated water near mining sites. The analyses reveal that UVI adsorbs at two distinct heights of 2.4-3.2 and 5-5.3 Å from the surface terminal oxygens. The former is interpreted as the mixture of inner-sphere and outer-sphere complexes that adsorb closest to the surface. The latter is interpreted as an outer-sphere complex that shares one equatorial H2O with the terminal surface oxygen. With increasing pH, we observe an increasing prevalence of these outer-sphere complexes, indicating the enhanced role of the hydrogen bond that stabilizes adsorbed uranyl species. The presented work provides a molecular-scale understanding of sorption of uranyl on Al-based-oxide surfaces that has implications for environmental chemistry and materials science.
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Affiliation(s)
- Julia Neumann
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Amanda J Carr
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Jessica Lessing
- Institute of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - L Soderholm
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Jeffrey G Catalano
- Department of Earth, Environmental, and Planetary Sciences, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Paul Fenter
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Sang Soo Lee
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
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Scheinost AC, Claussner J, Exner J, Feig M, Findeisen S, Hennig C, Kvashnina KO, Naudet D, Prieur D, Rossberg A, Schmidt M, Qiu C, Colomp P, Cohen C, Dettona E, Dyadkin V, Stumpf T. ROBL-II at ESRF: a synchrotron toolbox for actinide research. JOURNAL OF SYNCHROTRON RADIATION 2021; 28:333-349. [PMID: 33399586 PMCID: PMC7842221 DOI: 10.1107/s1600577520014265] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 10/26/2020] [Indexed: 05/06/2023]
Abstract
ROBL-II provides four different experimental stations to investigate actinide and other alpha- and beta-emitting radionuclides at the new EBS storage ring of ESRF within an energy range of 3 to 35 keV. The XAFS station consists of a highly automatized, high sample throughput installation in a glovebox, to measure EXAFS and conventional XANES of samples routinely at temperatures down to 10 K, and with a detection limit in the sub-p.p.m. range. The XES station with its five bent-crystal analyzer, Johann-type setup with Rowland circles of 1.0 and 0.5 m radii provides high-energy resolution fluorescence detection (HERFD) for XANES, XES, and RIXS measurements, covering both actinide L and M edges together with other elements accessible in the 3 to 20 keV energy range. The six-circle heavy duty goniometer of XRD-1 is equipped for both high-resolution powder diffraction as well as surface-sensitive CTR and RAXR techniques. Single crystal diffraction, powder diffraction with high temporal resolution, as well as X-ray tomography experiments can be performed at a Pilatus 2M detector stage (XRD-2). Elaborate radioprotection features enable a safe and easy exchange of samples between the four different stations to allow the combination of several methods for an unprecedented level of information on radioactive samples for both fundamental and applied actinide and environmental research.
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Affiliation(s)
- Andreas C. Scheinost
- The Rossendorf Beamline (BM20), European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
- Institute of Resource Ecology, Helmholtz Zentrum Dresden Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Juergen Claussner
- Department of Research Technology, Helmholtz Zentrum Dresden Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Joerg Exner
- The Rossendorf Beamline (BM20), European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
- Institute of Resource Ecology, Helmholtz Zentrum Dresden Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Manuel Feig
- The Rossendorf Beamline (BM20), European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
- Institut für Experimentelle Physik, TU Bergakademie Freiberg, 09596 Freiberg, Germany
| | - Stefan Findeisen
- Department of Research Technology, Helmholtz Zentrum Dresden Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Christoph Hennig
- The Rossendorf Beamline (BM20), European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
- Institute of Resource Ecology, Helmholtz Zentrum Dresden Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Kristina O. Kvashnina
- The Rossendorf Beamline (BM20), European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
- Institute of Resource Ecology, Helmholtz Zentrum Dresden Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Damien Naudet
- The Rossendorf Beamline (BM20), European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
- Institute of Resource Ecology, Helmholtz Zentrum Dresden Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Damien Prieur
- The Rossendorf Beamline (BM20), European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
- Institute of Resource Ecology, Helmholtz Zentrum Dresden Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Andre Rossberg
- The Rossendorf Beamline (BM20), European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
- Institute of Resource Ecology, Helmholtz Zentrum Dresden Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Moritz Schmidt
- Institute of Resource Ecology, Helmholtz Zentrum Dresden Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Canrong Qiu
- Institute of Resource Ecology, Helmholtz Zentrum Dresden Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Patrick Colomp
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
| | - Cedric Cohen
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
| | - Eric Dettona
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
| | - Vadim Dyadkin
- Swiss Norwegian Beamlines, European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
| | - Thorsten Stumpf
- Institute of Resource Ecology, Helmholtz Zentrum Dresden Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
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Schmidt M, Lee SS, Wilson RE, Knope KE, Bellucci F, Eng PJ, Stubbs JE, Soderholm L, Fenter P. Surface-mediated formation of Pu(IV) nanoparticles at the muscovite-electrolyte interface. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:14178-14184. [PMID: 24266655 DOI: 10.1021/es4037258] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The formation of Pu(IV)-oxo-nanoparticles from Pu(III) solutions by a surface-enhanced redox/polymerization reaction at the muscovite (001) basal plane is reported, with a continuous increase in plutonium coverage observed in situ over several hours. The sorbed Pu extends >70 Å from the surface with a maximum concentration at 10.5 Å and a total coverage of >9 Pu atoms per unit cell area of muscovite (0.77 μg Pu/cm(2)) (determined independently by in situ resonant anomalous X-ray reflectivity and by ex-situ alpha-spectrometry). The presence of discrete nanoparticles is confirmed by high resolution atomic force microscopy. We propose that the formation of these Pu(IV) nanoparticles from an otherwise stable Pu(III) solution can be explained by the combination of a highly concentrated interfacial Pu-ion species, the Pu(III)-Pu(IV) redox equilibrium, and the strong proclivity of tetravalent Pu to hydrolyze and form polymeric species. These results are the first direct observation of such behavior of plutonium on a naturally occurring mineral, providing insights into understanding the environmental transport of plutonium and other contaminants capable of similar redox/polymerization reactions.
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Affiliation(s)
- Moritz Schmidt
- Chemical Sciences and Engineering Division, Argonne National Laboratory , Argonne , Illinois 60439, United States
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Singer DM, Chatman SM, Ilton ES, Rosso KM, Banfield JF, Waychunas GA. U(VI) sorption and reduction kinetics on the magnetite (111) surface. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:3821-3830. [PMID: 22394451 DOI: 10.1021/es203878c] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Sorption of contaminants onto mineral surfaces is an important process that can restrict their transport in the environment. In the current study, uranium (U) uptake on magnetite (111) was measured as a function of time and solution composition (pH, [CO(3)](T), [Ca]) under continuous batch-flow conditions. We observed, in real-time and in situ, adsorption and reduction of U(VI) and subsequent growth of UO(2) nanoprecipitates using atomic force microscopy (AFM) and newly developed batch-flow U L(III)-edge grazing-incidence X-ray absorption spectroscopy near-edge structure (GI-XANES) spectroscopy. U(VI) reduction occurred with and without CO(3) present, and coincided with nucleation and growth of UO(2) particles. When Ca and CO(3) were both present no U(VI) reduction occurred and the U surface loading was lower. In situ batch-flow AFM data indicated that UO(2) particles achieved a maximum height of 4-5 nm after about 8 h of exposure, however, aggregates continued to grow laterally after 8 h reaching up to about 300 nm in diameter. The combination of techniques indicated that U uptake is divided into three-stages; (1) initial adsorption of U(VI), (2) reduction of U(VI) to UO(2) nanoprecipitates at surface-specific sites after 2-3 h of exposure, and (3) completion of U(VI) reduction after ~6-8 h. U(VI) reduction also corresponded to detectable increases in Fe released to solution and surface topography changes. Redox reactions are proposed that explicitly couple the reduction of U(VI) to enhanced release of Fe(II) from magnetite. Although counterintuitive, the proposed reaction stoichiometry was shown to be largely consistent with the experimental results. In addition to providing molecular-scale details about U sorption on magnetite, this work also presents novel advances for collecting surface sensitive molecular-scale information in real-time under batch-flow conditions.
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Affiliation(s)
- David M Singer
- Department Earth & Planetary Sciences, University of California, Berkeley, CA, USA.
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