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Barbhuiya S, Das BB, Qureshi T, Adak D. Cement-based solidification of nuclear waste: Mechanisms, formulations and regulatory considerations. J Environ Manage 2024; 356:120712. [PMID: 38531127 DOI: 10.1016/j.jenvman.2024.120712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 03/10/2024] [Accepted: 03/19/2024] [Indexed: 03/28/2024]
Abstract
This review paper provides a comprehensive analysis of cement-based solidification and immobilisation of nuclear waste. It covers various aspects including mechanisms, formulations, testing and regulatory considerations. The paper begins by emphasizing the importance of nuclear waste management and the associated challenges. It explores the mechanisms and principles in cement-based solidification, with a particular focus on the interaction between cement and nuclear waste components. Different formulation considerations are discussed, encompassing factors such as cement types, the role of additives and modifiers. The review paper also examines testing and characterisation methods used to assess the physical, chemical and mechanical properties of solidified waste forms. Then the paper addresses the regulatory considerations and compliance requirements for cement-based solidification. The paper concludes by critically elaborating on the current challenges, emerging trends and future research needs in the field. Overall, this review paper offers a comprehensive overview of cement-based solidification, providing valuable insights for researchers, practitioners and regulatory bodies involved in nuclear waste management.
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Affiliation(s)
- Salim Barbhuiya
- Department of Engineering and Construction, University of East London, London, UK.
| | | | - Tanvir Qureshi
- Canadian Nuclear Laboratories Limited, Chalk River, ON, Canada; Department of Engineering Design and Mathematics, University of the West of England, Bristol, UK
| | - Dibyendu Adak
- Department of Civil Engineering, NIT Meghalaya, Shillong, India
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2
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Böse F, Wimmers A, Neugebauer J, Lösel T, Hermes T, Beppler J, Nickel MS, Morawe P, Weber M, von Hirschhausen C. Putting radioactive materials on the sustainability agenda: a report from a workshop on the sustainability of human-made radioactive materials held at the safeND Research Symposium 2023. Radiat Environ Biophys 2024; 63:1-6. [PMID: 38367061 PMCID: PMC10920201 DOI: 10.1007/s00411-024-01061-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 02/06/2024] [Indexed: 02/19/2024]
Abstract
This report summarizes the findings of a workshop held at the safeND Research Symposium and hosted by the German Federal Office for the Safety of Radioactive Waste Management (BASE) in Berlin in September 2023. The workshop aimed to channel perspectives from various fields of expertise to discuss key sustainability concepts in terms of radioactive waste management. Therefore, the report highlights that current sustainability concepts, such as the United Nations' Sustainable Development Goals (SDG) as well as the concept of Planetary Boundaries, neglect challenges arising from the production and storage of human-made radioactive materials. The workshop consisted of three group tasks. The first attempted at identifying the interrelations between "sustainability" and radioactive waste management. The second was to map the global nature of the challenges. The third took first steps to determine a human-made radioactive material as a potential planetary sub-boundary for "novel entities". All three groups identified valuable knowledge gaps that should be addressed by future research and concluded that radioactive waste management is underrepresented in these sustainability concepts.
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Affiliation(s)
- Fanny Böse
- Federal Office for the Safety of Nuclear Waste Management (BASE), Wegelystraße 8, 10623, Berlin, Germany
- Workgroup for Infrastructure Policy (WIP), Technical University of Berlin (TU Berlin), Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Alexander Wimmers
- Workgroup for Infrastructure Policy (WIP), Technical University of Berlin (TU Berlin), Straße des 17. Juni 135, 10623, Berlin, Germany.
- German Institute for Economic Research (DIW Berlin), Mohrenstraße 58, 10117, Berlin, Germany.
| | | | - Theresa Lösel
- TU Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Timo Hermes
- TU Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Jasmin Beppler
- TU Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | | | - Pauline Morawe
- TU Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | | | - Christian von Hirschhausen
- Workgroup for Infrastructure Policy (WIP), Technical University of Berlin (TU Berlin), Straße des 17. Juni 135, 10623, Berlin, Germany
- German Institute for Economic Research (DIW Berlin), Mohrenstraße 58, 10117, Berlin, Germany
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3
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Thorpe CL, Crawford R, Hand RJ, Radford JT, Corkhill CL, Pearce CI, Neeway JJ, Plymale AE, Kruger AA, Morris K, Boothman C, Lloyd JR. Microbial interactions with phosphorus containing glasses representative of vitrified radioactive waste. J Hazard Mater 2024; 462:132667. [PMID: 37839373 DOI: 10.1016/j.jhazmat.2023.132667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 09/21/2023] [Accepted: 09/27/2023] [Indexed: 10/17/2023]
Abstract
The presence of phosphorus in borosilicate glass (at 0.1 - 1.3 mol% P2O5) and in iron-phosphate glass (at 53 mol% P2O5) stimulated the growth and metabolic activity of anaerobic bacteria in model systems. Dissolution of these phosphorus containing glasses was either inhibited or accelerated by microbial metabolic activity, depending on the solution chemistry and the glass composition. The breakdown of organic carbon to volatile fatty acids increased glass dissolution. The interaction of microbially reduced Fe(II) with phosphorus-containing glass under anoxic conditions decreased dissolution rates, whereas the interaction of Fe(III) with phosphorus-containing glass under oxic conditions increased glass dissolution. Phosphorus addition to borosilicate glasses did not significantly affect the microbial species present, however, the diversity of the microbial community was enhanced on the surface of the iron phosphate glass. Results demonstrate the potential for microbes to influence the geochemistry of radioactive waste disposal environments with implication for wasteform durability.
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Affiliation(s)
- C L Thorpe
- Immobilization Science Laboratory, Sir Robert Hadfield Building, University of Sheffield, S1 3JD, UK.
| | - R Crawford
- Immobilization Science Laboratory, Sir Robert Hadfield Building, University of Sheffield, S1 3JD, UK
| | - R J Hand
- Immobilization Science Laboratory, Sir Robert Hadfield Building, University of Sheffield, S1 3JD, UK
| | - J T Radford
- Immobilization Science Laboratory, Sir Robert Hadfield Building, University of Sheffield, S1 3JD, UK
| | - C L Corkhill
- Immobilization Science Laboratory, Sir Robert Hadfield Building, University of Sheffield, S1 3JD, UK; School of Earth Sciences, The University of Bristol, Bristol, UK
| | - C I Pearce
- Pacific Northwest National Laboratory, Richland, WA, USA
| | - J J Neeway
- Pacific Northwest National Laboratory, Richland, WA, USA
| | - A E Plymale
- Pacific Northwest National Laboratory, Richland, WA, USA
| | - A A Kruger
- Office of River Protection, US Department of Energy, Richland, WA, USA
| | - K Morris
- Williamson Research Centre and Research Centre for Radwaste Disposal, Williamson Building, University of Manchester, 176 Oxford Road, M13 9PL, UK
| | - C Boothman
- Williamson Research Centre and Research Centre for Radwaste Disposal, Williamson Building, University of Manchester, 176 Oxford Road, M13 9PL, UK
| | - J R Lloyd
- Williamson Research Centre and Research Centre for Radwaste Disposal, Williamson Building, University of Manchester, 176 Oxford Road, M13 9PL, UK
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Shirai K, Takada M, Murakami M, Ohnuma S, Yamada K, Osako M, Yasutaka T. Factors influencing acceptability of final disposal of incinerated ash and decontaminated soil from TEPCO's Fukushima Daiichi nuclear power plant accident. J Environ Manage 2023; 345:118610. [PMID: 37536131 DOI: 10.1016/j.jenvman.2023.118610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/30/2023] [Accepted: 07/08/2023] [Indexed: 08/05/2023]
Abstract
TEPCO's Fukushima Daiichi nuclear power plant accident prompted extensive decontamination work. The decontaminated soil and incinerated ash generated by the process are scheduled for final disposal by March 2045 outside Fukushima Prefecture. The final disposal is unprecedented worldwide. Clarifying their acceptability will contribute to the final disposal of decontaminated soil and incinerated ash, as well as add knowledge about the perceived risk of low-concentration radioactive waste. A questionnaire survey was conducted to assess the psychological factors influencing final disposal acceptability. The results of the structural equation modeling demonstrated stable results, with risk perception decreasing acceptability, social benefits increasing acceptability, and personal benefits having limited impact. The initiative for the final disposal of decontaminated soil and incinerated ash can facilitate the reconstruction of Fukushima Prefecture after the disaster. Trust and intergenerational expectations are critical factors influencing the acceptability of this disposal. The responses were classified based on the relevance of moral norms using cluster analysis and moral foundations. The influence of each element on acceptability varied depending on the cluster. Trust was identified as the most influential factor in acceptability, regardless of the level of importance placed on moral norms.
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Affiliation(s)
- Kosuke Shirai
- Research Institute for Geo-Resources and Environment, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8567, Japan; Social Safety and Industrial Innovation Division, Mitsubishi Research Institute, Inc., 10-3, Nagatacho 2-chome, Chiyoda-ku, Tokyo, 100-8141, Japan.
| | - Momo Takada
- Research Institute for Geo-Resources and Environment, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8567, Japan
| | - Michio Murakami
- Center for Infectious Disease Education and Research, Osaka University, 2-8 Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Susumu Ohnuma
- Department of Behavioral Science, Faculty of Humanities and Human Sciences, Hokkaido University, Kita 10 Nishi 7, Kita-ku, Sapporo, Hokkaido, 060-0810, Japan
| | - Kazuo Yamada
- Fukushima Regional Collaborative Research Center, National Institute for Environmental Studies, 10-2 Fukasaku, Miharu, Tamura District, Fukushima, 963-7700, Japan
| | - Masahiro Osako
- Material Cycles Division, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan
| | - Tetsuo Yasutaka
- Research Institute for Geo-Resources and Environment, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8567, Japan
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Kalintsev A, Guan Q, Brugger J, Migdisov A, Etschmann B, Ram R, Liu W, Mei Y, Testemale D, Xu H. Nature and coordination geometry of geologically relevant aqueous Uranium(VI) complexes up to 400 ºC: A review and new data. J Hazard Mater 2023; 452:131309. [PMID: 37018892 DOI: 10.1016/j.jhazmat.2023.131309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Revised: 03/23/2023] [Accepted: 03/26/2023] [Indexed: 06/19/2023]
Abstract
The structure of the uranyl aqua ion (UO22+) and a number of its inorganic complexes (specifically, UO2Cl+, UO2Cl20, UO2SO40, [Formula: see text] , [Formula: see text] and UO2OH42-) have been characterised using X-Ray absorption spectroscopy/extended X-Ray absorption fine structure (XAS/EXAFS) at temperatures ranging from 25 to 326 ºC. Results of ab initio molecular dynamics (MD) calculations are also reported for uranyl in chloride and sulfate-bearing fluids from 25 to 400 ºC and 600 bar to 20 kilobar (kb). These results are reported alongside a comprehensive review of prior structural characterisation work with particular focus given to EXAFS works to provide a consistent and up-to-date view of the structure of these complexes under conditions relevant to U mobility in ore-forming systems and around high-grade nuclear waste repositories. Regarding reported EXAFS results, average equatorial coordination was found to decrease in uranyl and its sulfate and chloride complexes as temperature rose - the extent of this decrease differed between species and solution compositions but typically resulted in an equatorial coordination number of ∼3-4 at temperatures above 200 ºC. The [Formula: see text] complex was observed at temperatures from 25 to 247 ºC and exhibited no major structural changes over this temperature range. UO2OH42- exhibited only minor structural changes over a temperature range from 88 to 326 ºC and was suggested to manifest fivefold coordination with four hydroxyl molecules and one water molecule around its equator. Average coordination values derived from fits of the reported EXAFS data were compared to average coordination values calculated using the experimentally derived thermodynamic data for chloride complexes reported by Dargent et al. (2013) and Migdisov et al. (2018b), and for sulfate complexes reported by Alcorn et al. (2019) and Kalintsev et al. (2019). Sulfate EXAFS data were well described by available thermodynamic data, and chloride EXAFS data were described well by the thermodynamic data of Migdisov et al. (2018b), but not by the data of Dargent et al. (2013). The ab initio molecular dynamics calculations confirmed the trends in equatorial coordination observed with EXAFS and were also able to provide an insight into the effect of pressure in equatorial water coordination - for a given temperature, higher pressures appear to lead to a greater number of equatorially bound waters counteracting the temperature effect.
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Affiliation(s)
- Alexander Kalintsev
- School of Earth, Atmosphere and Environment, Monash University, 9 Rainforest Walk, VIC 3800, Australia; Los Alamos National Laboratory, Earth & Environmental Division, Los Alamos, NM, USA.
| | - Qiushi Guan
- CSIRO Mineral Resources, Kensington, WA 6151, Australia
| | - Joël Brugger
- School of Earth, Atmosphere and Environment, Monash University, 9 Rainforest Walk, VIC 3800, Australia
| | - Artas Migdisov
- Los Alamos National Laboratory, Earth & Environmental Division, Los Alamos, NM, USA
| | - Barbara Etschmann
- School of Earth, Atmosphere and Environment, Monash University, 9 Rainforest Walk, VIC 3800, Australia
| | - Rahul Ram
- School of Earth, Atmosphere and Environment, Monash University, 9 Rainforest Walk, VIC 3800, Australia
| | - Weihua Liu
- CSIRO Mineral Resources, Kensington, WA 6151, Australia
| | - Yuan Mei
- CSIRO Mineral Resources, Kensington, WA 6151, Australia
| | - Denis Testemale
- CNRS, Université Grenoble Alpes, Institut NEEL, Grenoble F-38000, France
| | - Hongwu Xu
- Los Alamos National Laboratory, Earth & Environmental Division, Los Alamos, NM, USA
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Laloy E, Rogiers B, Bielen A, Borella A, Boden S. Improving Bayesian radiological profiling of waste drums using Dirichlet priors, Gaussian process priors, and hierarchical modeling. Appl Radiat Isot 2023; 194:110691. [PMID: 36716689 DOI: 10.1016/j.apradiso.2023.110691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 12/07/2022] [Accepted: 01/21/2023] [Indexed: 01/26/2023]
Abstract
We present three methodological improvements of our recently proposed approach for Bayesian inference of the radionuclide inventory in radioactive waste drums, from radiological measurements. First we resort to the Dirichlet distribution for the prior distribution of the isotopic vector. The Dirichlet distribution possesses the attractive property that the elements of its vector samples sum up to 1. Second, we demonstrate that such Dirichlet priors can be incorporated within an hierarchical modeling of the prior uncertainty in the isotopic vector, when prior information about isotopic composition is available. Our used Bayesian hierarchical modeling framework makes use of this available information but also acknowledges its uncertainty by letting to a controlled extent the information content of the indirect measurement data (i.e., gamma and neutron counts) shape the actual prior distribution of the isotopic vector. Third, we propose to regularize the Bayesian inversion by using Gaussian process (GP) prior modeling when inferring 1D spatially-distributed mass or, equivalently, activity distributions. As of uncertainty in the efficiencies, we keep using the same stylized drum modeling approach as proposed in our previous work to account for the source distribution uncertainty across the vertical direction of the drum. A series of synthetic tests followed by application to a real waste drum show that combining hierarchical modeling of the prior isotopic composition uncertainty together with GP prior modeling of the vertical Pu profile across the drum works well. We also find that our GP prior can handles both cases with and without spatial correlation. Of course, our GP prior modeling framework only makes sense in the context of spatial inference. Furthermore, the computational times involved by our approach are on the order of a few hours, say about 2, to provide uncertainty estimates for all variables of interest in the considered inverse problem. This warrants further investigations to speed up the inference.
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Affiliation(s)
- Eric Laloy
- Waste and Disposal, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre (SCK CEN), Belgium.
| | - Bart Rogiers
- Waste and Disposal, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre (SCK CEN), Belgium.
| | - An Bielen
- Dismantling, Decontamination and Waste, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre (SCK CEN), Belgium.
| | - Alessandro Borella
- Society and Policy Support, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre (SCK CEN), Belgium.
| | - Sven Boden
- Dismantling, Decontamination and Waste, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre (SCK CEN), Belgium.
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7
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Llopart-Babot I, Vasile M, Tarancón A, Bagán H, Dobney A, Boden S, Bruggeman M, Leermakers M, Qiao J, Warwick P. Investigation of a new approach for 36Cl determination in solid samples using plastic scintillators. Appl Radiat Isot 2023; 193:110646. [PMID: 36603458 DOI: 10.1016/j.apradiso.2022.110646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/23/2022] [Accepted: 12/30/2022] [Indexed: 01/01/2023]
Abstract
This work reports a new approach for the determination of 36Cl in radioactive waste samples from nuclear decommissioning, wherein novel plastic scintillator (PS) materials were used for the concentration of 36Cl prior to the detection with scintillation counting. Different plastic scintillator (PS) materials were tested for their selective absorption and detection of 36Cl activity in solid samples. PS microspheres (PSm), cross-linked PSm (CPSm) and PS resin have been investigated. PS resin was identified as the most suitable material for 36Cl analysis. Pyrolysis and subsequent trapping of the volatile elements in a bubbler was used. The trapping solution was finally loaded onto a cartridge of the PS resin. Scintillation counting and ion chromatography were used to determine the activity concentration and the chemical recovery, respectively.
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Affiliation(s)
- I Llopart-Babot
- SCK CEN, Boeretang 200, 2400, Mol, Belgium; VUB, AMGC, Pleinlaan 2, 1050, Brussels, Belgium.
| | - M Vasile
- SCK CEN, Boeretang 200, 2400, Mol, Belgium
| | - A Tarancón
- Departament d'Enginyeria Química i Química Analítica, Universitat de Barcelona, Marti i Franqués, 1-11, 08028, Barcelona, Spain
| | - H Bagán
- Departament d'Enginyeria Química i Química Analítica, Universitat de Barcelona, Marti i Franqués, 1-11, 08028, Barcelona, Spain
| | - A Dobney
- SCK CEN, Boeretang 200, 2400, Mol, Belgium
| | - S Boden
- SCK CEN, Boeretang 200, 2400, Mol, Belgium
| | | | | | - J Qiao
- Department of Environmental and Resource Engineering, Technical University of Denmark, Frederiksborgvej 399, 4000, Roskilde, Denmark
| | - P Warwick
- University of Southampton, National Oceanography Centre, Southampton, European Way, Southampton, SO14 3ZH, UK
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Montavon G, Ribet S, Loni YH, Maia F, Bailly C, David K, Lerouge C, Madé B, Robinet JC, Grambow B. Uranium retention in a Callovo-Oxfordian clay rock formation: From laboratory-based models to in natura conditions. Chemosphere 2022; 299:134307. [PMID: 35339522 DOI: 10.1016/j.chemosphere.2022.134307] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/08/2022] [Accepted: 03/11/2022] [Indexed: 06/14/2023]
Abstract
For the performance assessment of radioactive waste disposal, it is critical to predict the mobility of radionuclides in the geological barrier that hosts it. A key challenge consists of assessing the transferability of current knowledge on the retention properties deduced from model systems to in natura situations. The case of the redox-sensitive element uranium in the Callovo-Oxfordian clay formation (COx) is presented herein. Extensive experimental work was carried out with respect to parameters affecting uranium speciation (pH, PCO2, [Ca] and redox potential) with illite, COx clay fraction and raw COx claystone. The "bottom-up" approach implemented, with illite and montmorillonite as reactive phases, quantitatively explains the adsorption results of U(VI) and U(IV) on COx. While retention is high for U(IV) (Rd∼104 L kg-1), it remains very low for U(VI) (Rd∼4 L kg-1) due to the formation of soluble ternary Ca(Mg)-U(VI)-carbonate complexes. The applicability of the sorption model was then assessed by comparing predictive analyses with data characterizing the behavior of naturally-occurring U (<3 mg kg-1). The COx clay phase is the largest reservoir of naturally-occurring U (∼65%) but only a small fraction appears to be adsorbed (∼1%). Under representative site conditions (especially with respect to reducing conditions), we have concluded that ternary U(VI) complexes control U speciation in solution while U(IV) surface species dominate U adsorption, with Rd values > 70 L kg-1.
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Affiliation(s)
- G Montavon
- SUBATECH, IMTA/CNRS-IN2P3/Université de Nantes, 4, rue Alfred Kastler, F- 44304, Nantes, France.
| | - S Ribet
- SUBATECH, IMTA/CNRS-IN2P3/Université de Nantes, 4, rue Alfred Kastler, F- 44304, Nantes, France
| | - Y Hassan Loni
- SUBATECH, IMTA/CNRS-IN2P3/Université de Nantes, 4, rue Alfred Kastler, F- 44304, Nantes, France
| | - F Maia
- SUBATECH, IMTA/CNRS-IN2P3/Université de Nantes, 4, rue Alfred Kastler, F- 44304, Nantes, France
| | - C Bailly
- SUBATECH, IMTA/CNRS-IN2P3/Université de Nantes, 4, rue Alfred Kastler, F- 44304, Nantes, France
| | - K David
- SUBATECH, IMTA/CNRS-IN2P3/Université de Nantes, 4, rue Alfred Kastler, F- 44304, Nantes, France
| | - C Lerouge
- BRGM, 3 avenue Claude Guillemin, F-45060, Orléans, France
| | - B Madé
- ANDRA, 1/7 rue Jean Monnet, Parc de la Croix-Blanche, F-92298, Châtenay-Malabry, France
| | - J C Robinet
- ANDRA, 1/7 rue Jean Monnet, Parc de la Croix-Blanche, F-92298, Châtenay-Malabry, France
| | - B Grambow
- SUBATECH, IMTA/CNRS-IN2P3/Université de Nantes, 4, rue Alfred Kastler, F- 44304, Nantes, France
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9
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Bourchy A, Saslow SA, Williams BD, Avalos NM, Um W, Canfield NL, Sweet L, Smith GL, Asmussen RM. The evolution of hydrated lime-based cementitious waste forms during leach testing leading to enhanced technetium retention. J Hazard Mater 2022; 430:128507. [PMID: 35739685 DOI: 10.1016/j.jhazmat.2022.128507] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 02/10/2022] [Accepted: 02/15/2022] [Indexed: 06/15/2023]
Abstract
The interaction between radionuclides and cementitious material phases is crucial in the prediction of the long-term disposal behavior of cementitious waste forms. This work focuses on the behavior of technetium-99 (Tc) within a hydrated-lime based waste form developed as a candidate to immobilize high-sulphate containing liquid wastes known to inhibit cement solidification when using a fly ash based formulation. In leach testing, the hydrated-lime based formulation demonstrated improvement in Tc retention over a fly ash containing formulation beginning after 14 d leaching. The mineralogical evolution of the hydrated-lime samples during leach testing showed a decrease in portlandite content and reduction capacity at the onset of the Tc retention improvement. Leach testing upwards of 400 days showed the improved Tc retention was sustained. Samples cured for different lengths of time (28 days vs 60 days) confirmed that the improved Tc retention and mineralogic change was caused by cement - leachant interactions and not the sample curing time. The Tc observed diffusivities in the hydrated-lime samples are amongst the lowest measured in a cement waste form tested for development at the US Department of Energy Hanford site, leading to a possible pathway to improved cement conditioning where contaminants can be retained for long disposal times.
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Affiliation(s)
- Agathe Bourchy
- Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Sarah A Saslow
- Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Benjamin D Williams
- Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Nancy M Avalos
- Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Wooyong Um
- Pohang University of Science and Technology, Pohang, South Korea
| | - Nathan L Canfield
- Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Lucas Sweet
- Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Gary L Smith
- Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, WA, USA
| | - R Matthew Asmussen
- Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, WA, USA.
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10
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Tolan DA, Elshehy EA, El-Said WA, Taketsugu T, Yoshizawa K, El-Nahas AM, Kamali AR, Abdelkader AM. Cubically cage-shaped mesoporous ordered silica for simultaneous visual detection and removal of uranium ions from contaminated seawater. Mikrochim Acta 2021; 189:3. [PMID: 34855016 DOI: 10.1007/s00604-021-05083-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 10/25/2021] [Indexed: 12/14/2022]
Abstract
A dual-function organic-inorganic mesoporous structure is reported for naked-eye detection and removal of uranyl ions from an aqueous environment. The mesoporous sensor/adsorbent is fabricated via direct template synthesis of highly ordered silica monolith (HOM) starting from a quaternary microemulsion liquid crystalline phase. The produced HOM is subjected to further modifications through growing an organic probe, omega chrome black blue G (OCBBG), in the cavities and on the outer surface of the silica structure. The spectral response for [HOM-OCBBG → U(VI)] complex shows a maximum reflectance at λmax = 548 nm within 1 min response time (tR); the LOD is close to 9.1 μg/L while the LOQ approaches 30.4 μg/L, and this corresponds to the range of concentration where the signal is linear against U(VI) concentration (i.e., 5-1000 μg/L) at pH 3.4 with standard deviation (SD) of 0.079 (RSD% = 11.7 at n = 10). Experiments and DFT calculations indicate the existence of strong binding energy between the organic probe and uranyl ions forming a complex with blue color that can be detected by naked eyes even at low uranium concentrations. With regard to the radioactive remediation, the new mesoporous sensor/captor is able to reach a maximum capacity of 95 mg/g within a few minutes of the sorption process. The synthesized material can be regenerated using simple leaching and re-used several times without a significant decrease in capacity.
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Affiliation(s)
- Dina A Tolan
- Department of Chemistry, College of Science and Humanities, Prince Sattam bin Abdulaziz University, Alkharj, 11942, Saudi Arabia.,Chemistry Department, Faculty of Science, Menoufia University, Menoufia, Egypt
| | | | - Waleed A El-Said
- Department of Chemistry, Faculty of Science, Assiut University, Assiut, 71516, Egypt.,Department of Chemistry, College of Science, University of Jeddah, P.O. Box 80327, Jeddah, 21589, Saudi Arabia
| | - Tetsuya Taketsugu
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, 060-0810, Japan.,Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo, 060-0810, Japan
| | - Kazunari Yoshizawa
- Institute for Materials Chemistry and Engineering, Kyushu University, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Ahmed M El-Nahas
- Department of Chemistry, College of Science and Humanities, Prince Sattam bin Abdulaziz University, Alkharj, 11942, Saudi Arabia
| | - Ali Reza Kamali
- Energy and Environmental Materials Research Centre (E2MC), School of Metallurgy, Northeastern University, Shenyang, 110819, People's Republic of China
| | - Amr M Abdelkader
- Department of Engineering, Bournemouth University, Talbot Campus, Fern Barrow, Poole, BH12 5BB, UK.
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11
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Nezhad MM, Semnani A, Tavakkoli N, Shirani M. Selective and highly efficient removal of uranium from radioactive effluents by activated carbon functionalized with 2-aminobenzoic acid as a new sorbent. J Environ Manage 2021; 299:113587. [PMID: 34479154 DOI: 10.1016/j.jenvman.2021.113587] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/16/2021] [Accepted: 08/20/2021] [Indexed: 06/13/2023]
Abstract
The purpose of this study was modification of activated carbon (AC) to prepare a new selective sorbent for removal of uranium ion. The modification was performed by introducing carboxyl groups onto AC using ammonium persulfate (APS) in sulfuric acid solution followed by functionalization with 2-aminobenzoic acid (ABA) as a selective ligand for U (VI) ion (UO22+) adsorption. The characterization of the synthetized sorbent (AC-ABA) was carried out through several methods including potentiometry, scanning electron microscopy, energy dispersive spectroscopy, x-ray diffraction and FT-IR to confirm successful functionalization of the sorbent surface with oxygen and amine groups. The sorption of U (VI) on the unmodified AC and AC-ABA was investigated as a function of contact time, sorbent content, initial uranium concentration, solution pH, and temperature using batch sorption technique. In addition, the effect of various parameters on the U (VI) sorption capacity was optimized by the response surface methodology as a potent experimental design method. The results indicated that sorption of U (VI) under the optimal conditions was significantly improved onto AC-ABA compared to AC. Kinetic studies displayed that the sorption process reached equilibrium after 100 min and followed the pseudo-second-order rate equation. The isothermal data fitted better with the Langmuir model than the Freundlich model. The maximum sorption capacity of AC-ABA for U(VI) was obtained to be 194.2 mg g-1 by the Langmuir model under optimum conditions, which demonstrates the sorption capacity has been improved by the modification process. The thermodynamic parameters (ΔH, ΔS and ΔG) indicated that sorption of uranium onto AC-ABA was an endothermic and spontaneous process. The sorption studies on radioactive effluents of the nuclear fuel plant represented high selectivity of AC-ABA for removal of uranium in the presence of other metal ions, and the selectivity coefficients significantly improved after modification of the sorbent. Application of AC-ABA for treatment of industrial effluents containing heavy and radioactive metal ions show high potential and capability of the proposed method.
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Affiliation(s)
- Majid Mohammad Nezhad
- Department of Chemistry, Faculty of Science, Shahrekord University, Shahrekord, P.O. Box 115, Iran
| | - Abolfazl Semnani
- Department of Chemistry, Faculty of Science, Shahrekord University, Shahrekord, P.O. Box 115, Iran.
| | - Nahid Tavakkoli
- Chemistry Department, Payame Noor University, Tehran, 19395-4697, Iran
| | - Mahboube Shirani
- Department of Chemistry, Faculty of Science, University of Jiroft, Jiroft, P. O. Box 7867161167, Iran.
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12
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Lawter AR, Levitskaia TG, Qafoku O, Bowden ME, Colon FC, Qafoku NP. Simultaneous immobilization of aqueous co-contaminants using a bismuth layered material. J Environ Radioact 2021; 237:106711. [PMID: 34388522 DOI: 10.1016/j.jenvrad.2021.106711] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 07/29/2021] [Accepted: 07/30/2021] [Indexed: 06/13/2023]
Abstract
The remediation of co-located contaminants in the vadose zone can be challenging due to accessibility and responses of different contaminants to remedial actions. At the Hanford Site (WA, USA), multiple radionuclides and other hazardous contaminants are present in the vadose zone and groundwater, including iodine-129 (I), technetium-99 (Tc), uranium-238 (U), chromium (Cr), and nitrate (NO3-). We evaluated a layered Bi oxyhydroxide material for its potential to remove individual and co-located contaminants with a series of batch experiments that investigated a range of plume conditions, followed by solid phase characterization of the reacted bismuth material. The results demonstrated successful removal of four contaminants (>98% removal of I, Tc, U, and Cr from the aqueous phase after 30 days) when tested individually. When contaminants were combined, a slight decrease in Tc removal occurred (-6%p). The addition of sediment decreased the removal for Tc and I, but U and Cr removal was unaffected. The results of these batch tests demonstrated that the bismuth based oxy-hydroxide material is a promising material for sequestering multiple contaminants in situ.
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Affiliation(s)
- Amanda R Lawter
- Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, Richland, WA, USA, 99352.
| | - Tatiana G Levitskaia
- Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, Richland, WA, USA, 99352
| | - Odeta Qafoku
- Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, Richland, WA, USA, 99352
| | - Mark E Bowden
- Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, Richland, WA, USA, 99352
| | - Ferdinan Cintron Colon
- Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, Richland, WA, USA, 99352
| | - Nikolla P Qafoku
- Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, Richland, WA, USA, 99352
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13
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Schönenbach D, Berg F, Breckheimer M, Hagenlocher D, Schönberg P, Haas R, Amayri S, Reich T. Development, characterization, and first application of a resonant laser secondary neutral mass spectrometry setup for the research of plutonium in the context of long-term nuclear waste storage. Anal Bioanal Chem 2021; 413:3987-3997. [PMID: 33973021 PMCID: PMC8189947 DOI: 10.1007/s00216-021-03350-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 03/21/2021] [Accepted: 04/14/2021] [Indexed: 11/26/2022]
Abstract
Plutonium is a major contributor to the radiotoxicity in a long-term nuclear waste repository; therefore, many studies have focused on interactions of plutonium with the technical, geotechnical, and geological barriers of a possible nuclear waste storage site. In order to gain new insights into the sorption on surfaces and diffusion of actinides through these complex heterogeneous materials, a highly sensitive method with spatial resolution is required. Resonant laser secondary neutral mass spectrometry (Laser-SNMS) uses the spatial resolution available in time-of-flight secondary ion mass spectrometry (TOF-SIMS) in combination with the high selectivity, sensitivity, and low background noise of resonance ionization mass spectrometry (RIMS) and is, therefore, a promising method for the study and analysis of the geochemical behavior of plutonium in long-term nuclear waste storage. The authors present an approach with a combined setup consisting of a commercial TOF-SIMS instrument and a Ti:sapphire (Ti:Sa) laser system, as well as its optimization, characterization, and improvements compared to the original proof of concept by Erdmann et al. (2009). As a first application, the spatial distributions of plutonium and other elements on the surface of a pyrite particle and a cement thin section were measured by Laser-SNMS and TOF-SIMS, respectively. These results exemplify the potential of these techniques for the surface analysis of heterogeneous materials in the context of nuclear safety research.
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Affiliation(s)
- Daniela Schönenbach
- Department of Chemistry, Johannes Gutenberg-Universität Mainz, 55099, Mainz, Germany
| | - Felix Berg
- Department of Chemistry, Johannes Gutenberg-Universität Mainz, 55099, Mainz, Germany
| | - Markus Breckheimer
- Department of Chemistry, Johannes Gutenberg-Universität Mainz, 55099, Mainz, Germany
| | - Daniel Hagenlocher
- Department of Chemistry, Johannes Gutenberg-Universität Mainz, 55099, Mainz, Germany
| | - Pascal Schönberg
- Department of Chemistry, Johannes Gutenberg-Universität Mainz, 55099, Mainz, Germany
| | - Raphael Haas
- Department of Chemistry, Johannes Gutenberg-Universität Mainz, 55099, Mainz, Germany
- Helmholtz-Institut Mainz, 55099, Mainz, Germany
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291, Darmstadt, Germany
| | - Samer Amayri
- Department of Chemistry, Johannes Gutenberg-Universität Mainz, 55099, Mainz, Germany
| | - Tobias Reich
- Department of Chemistry, Johannes Gutenberg-Universität Mainz, 55099, Mainz, Germany.
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14
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Wang Z, Walter ED, Sassi M, Zhang X, Zhang H, Li XS, Chen Y, Cui W, Tuladhar A, Chase Z, Winkelman AD, Wang HF, Pearce CI, Clark SB, Rosso KM. The role of surface hydroxyls on the radiolysis of gibbsite and boehmite nanoplatelets. J Hazard Mater 2020; 398:122853. [PMID: 32768813 DOI: 10.1016/j.jhazmat.2020.122853] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 04/30/2020] [Accepted: 05/01/2020] [Indexed: 06/11/2023]
Abstract
Understanding mechanistic pathways to radiolytic hydrogen generation by metal oxyhydroxide nanomaterials is challenging because of the difficulties of distinguishing key locations of OH bond scission, from structural interiors to hydroxylated surfaces to physi-sorbed water molecules. Here we exploited the interface-selectivity of vibrational sum frequency generation (VSFG) to isolate surface versus bulk hydroxyl groups for gibbsite and boehmite nanoplatelets before and after 60Co irradiation at dose levels of approximately 7.0 and 29.6 Mrad. While high-resolution microscopy revealed no effect on particle bulk and surface structures, VSFG results clearly indicated up to 83% and 94% radiation-induced surface OH bond scission for gibbsite and boehmite, respectively, a substantially higher proportion than observed for interior OH groups by IR and Raman spectroscopy. Electron paramagnetic spectroscopy revealed that the major radiolysis products bound in the mineral structures are trapped electrons, O, O2- and possibly F-centers in gibbsite, and H, O and O3- in boehmite, which persist on the time frame of several months. The entrapped radiolysis products appear to be highly stable, enduring re-hydration of particle surfaces, and likely reflect a permanent adjustment in the thermodynamic stabilities of these nanomaterials.
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Affiliation(s)
- Zheming Wang
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States.
| | - Eric D Walter
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Michel Sassi
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Xin Zhang
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Hailin Zhang
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Xiaohong S Li
- Energy and Environmental Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Ying Chen
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Wenwen Cui
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Aashish Tuladhar
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Zizwe Chase
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Austin D Winkelman
- Energy and Environmental Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States; Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, 220 Handan Road, Shanghai 200433, China
| | | | - Carolyn I Pearce
- Energy and Environmental Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Sue B Clark
- Energy and Environmental Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States; Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, 220 Handan Road, Shanghai 200433, China
| | - Kevin M Rosso
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
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15
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Castrillejo M, Witbaard R, Richardson CA, Dekker R, Welte C, Wacker L, Christl M. Impact of nuclear fuel reprocessing on the temporal evolution of marine radiocarbon. Sci Total Environ 2020; 738:139700. [PMID: 32534284 DOI: 10.1016/j.scitotenv.2020.139700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 05/23/2020] [Accepted: 05/23/2020] [Indexed: 06/11/2023]
Abstract
Radiocarbon (14C) is broadly used in oceanography to determine water ages, trace water circulation, and develop sediment- and sclerochronologies. These applications require an accurate knowledge of marine 14C levels, which have been largely perturbed by human activities. Globally during the last century the above-ground nuclear weapon testings have been the primary cause of the increased atmospheric and marine 14C. However, other anthropogenic sources may have caused important regional deviations from the bomb pulse. For the last 70 years European nuclear fuel reprocessing plants have been major contributors of 14C to air and oceans, yet, their regional impact on surrounding marine 14C has been largely overlooked. Here we use a collection of bivalve shells of known capture date and age collected from various locations, including the North Sea, the Irish Sea, Norway, and the Bay of Biscay to reconstruct the sea surface 14C over the last five decades. The measured 14C values for the period 1969-2019, reported in fraction modern, ranged from 1.1 to 1.6 in coastal waters of the Netherlands and from 1.2 to 3.2 along the coast of the UK, indicating significantly higher levels of 14C than those expected for the marine bomb pulse (0.950-1.150). The 14C peaks revealed by the shells coincide with the increase of liquid 14C releases reported from the reprocessing plants of La Hague into the English Channel, and from Sellafield into the Irish Sea. Conversely, the shells from Norway and Spain showed 14C values close to the range of the global marine bomb pulse. The observed large spatial and temporal differences in sea surface 14C show that 14C dating and tracing studies could become problematic in the English Channel, Irish Sea and North Sea for the time period covering the discharge of liquid 14C from the reprocessing plants.
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Affiliation(s)
- Maxi Castrillejo
- Laboratory of Ion Beam Physics, ETH - Zurich, Otto Stern Weg 5, 8093 Zurich, Switzerland.
| | - Rob Witbaard
- NIOZ Royal Netherlands Institute for Sea Research and Utrecht University, PO Box 59, 1790 AB Den Burg, the Netherlands
| | | | - Rob Dekker
- NIOZ Royal Netherlands Institute for Sea Research and Utrecht University, PO Box 59, 1790 AB Den Burg, the Netherlands
| | - Caroline Welte
- Laboratory of Ion Beam Physics, ETH - Zurich, Otto Stern Weg 5, 8093 Zurich, Switzerland; Biogeosciences, ETH - Zurich, Sonneggstrasse 5, 8092 Zurich, Switzerland
| | - Lukas Wacker
- Laboratory of Ion Beam Physics, ETH - Zurich, Otto Stern Weg 5, 8093 Zurich, Switzerland
| | - Marcus Christl
- Laboratory of Ion Beam Physics, ETH - Zurich, Otto Stern Weg 5, 8093 Zurich, Switzerland
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16
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Tse P, Bryan SA, Bessen NP, Lines AM, Shafer JC. Review of on-line and near real-time spectroscopic monitoring of processes relevant to nuclear material management. Anal Chim Acta 2020; 1107:1-13. [PMID: 32200882 DOI: 10.1016/j.aca.2020.02.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 02/01/2020] [Accepted: 02/03/2020] [Indexed: 11/21/2022]
Abstract
Spectroscopic chemometric based on-line monitoring of used nuclear fuel (UNF) reprocessing solutions and characterization of legacy nuclear waste (LNW) stored at Hanford is discussed in this manuscript. Utilizing on-line and near real-time monitoring, as opposed to traditional off-line monitoring, can significantly reduce the cost, risk and improve the efficiency of characterizing UNF and LNW processing streams. Specifically, this manuscript will highlight the benefits of spectroscopy-based monitoring approaches, which generally include the ability to collect data non-destructively. Furthermore, significant literature precedence supports the use of various real-time analysis methods, including chemometric analysis, that enable near-instantaneous conversion of spectroscopic data into information useable by process operators. This approach can accurately quantify and qualify nuclear material in near-real time enabling immediate condition characterization and potential diversion detection within UNF reprocessing streams and LNW. The ability to be applied in a real reprocessing plant and in an actual Hanford waste tank/transfer pipe has been demonstrated by applying this technique to accurately quantify analytes in real UNF streams and LNW samples. The future development of spectroscopy-based on-line monitoring is also discussed in this manuscript.
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17
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Paulillo A, Clift R, Dodds J, Milliken A, Palethorpe S, Lettieri P. Radiological impacts in Life Cycle Assessment - Part II: Comparison of methodologies. Sci Total Environ 2020; 708:134712. [PMID: 31740058 DOI: 10.1016/j.scitotenv.2019.134712] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 09/27/2019] [Accepted: 09/27/2019] [Indexed: 06/10/2023]
Abstract
In a complementary article, an overarching framework was proposed to include radiological impacts in Life Cycle Impact Assessment (LCIA). Two methodologies were derived embodying the framework: the Critical Group Methodology (CGM), adapted from the approach commonly used in Human and Environmental Risk Assessment (HERA), and UCrad, based on the compartment modelling approach commonly used in LCIA. In this paper, characterisation factors obtained by the two methodologies are compared in detail to investigate the consequences of the different approaches to fate modelling and the sensitivity of the characterisation factors to the radionuclides' half-life. Characterisation factors from the CGM methodology are strongly affected by radioactive decay at low half-life and by dilution at large distances. Conversely, UCrad factors are not affected by dilution and are affected less than CGM by radioactive decay. It is concluded that UCrad is more appropriate than CGM for LCA because it is consistent with the general approach used in LCIA. However, CGM can be used alongside UCrad to make recommendations on the location and scale of specific processes emitting radionuclides.
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Affiliation(s)
- Andrea Paulillo
- Department of Chemical Engineering, University College London, Torrington Place, London WC1 E7JE, United Kingdom.
| | - Roland Clift
- Centre for Environment and Sustainability, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
| | - Jonathan Dodds
- National Nuclear Laboratory, Workington, Cumbria CA14 3YQ, United Kingdom
| | - Andrew Milliken
- Ardskell, Embleton, Cockermouth, Cumbria CA13 9YP, United Kingdom
| | - Stephen Palethorpe
- National Nuclear Laboratory, Workington, Cumbria CA14 3YQ, United Kingdom
| | - Paola Lettieri
- Department of Chemical Engineering, University College London, Torrington Place, London WC1 E7JE, United Kingdom
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18
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Paulillo A, Clift R, Dodds JM, Milliken A, Palethorpe SJ, Lettieri P. Radiological impacts in Life Cycle Assessment. Part I: General framework and two practical methodologies. Sci Total Environ 2020; 708:135179. [PMID: 31806334 DOI: 10.1016/j.scitotenv.2019.135179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 10/21/2019] [Accepted: 10/23/2019] [Indexed: 06/10/2023]
Abstract
To date, impacts of ionising radiations have been largely disregarded in Life Cycle Assessment (LCA). This omission can be linked to the lack of a standard and comprehensive framework for including the effects of radionuclides alongside other emissions from industrial processes. Drawing on a recent review of Radiological Impact Assessment methodologies for LCA studies, this article proposes an overarching framework for integrating impacts of radionuclides in the Impact Assessment phase of LCA. From this framework, two alternative methodologies have been derived. They differ mainly in the way transport and dispersion of radionuclides in the environment are modelled: UCrad represents the first-of-its-kind compartment-type methodology for radionuclides, whereas the alternative Critical Group Methodology (CGM) has been adapted from standard Risk Assessment practices. Characterisation factors for a range of emitted species have been calculated using both methodologies and compared with those obtained from the Human Health Damages methodology, which is the only approach to radiological impacts yet implemented in LCA. For both UCrad and CGM the results are in general agreement with the Human Health Damages methodology, but UCrad gives factors closer to those obtained by the CGM approach. UCrad represents a major step towards incorporating ionising radiation impacts in LCIA. A subsequent paper will explore quantitatively the main differences between the UCrad and CGM methodologies.
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Affiliation(s)
- Andrea Paulillo
- Department of Chemical Engineering, University College London, Torrington Place, London WC1 E7JE, United Kingdom.
| | - Roland Clift
- Centre for Environment and Sustainability, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
| | - Jonathan M Dodds
- National Nuclear Laboratory, Workington, Cumbria CA14 3YQ, United Kingdom
| | - Andrew Milliken
- Ardskell, Embleton, Cockermouth, Cumbria CA13 9YP, United Kingdom
| | | | - Paola Lettieri
- Department of Chemical Engineering, University College London, Torrington Place, London WC1 E7JE, United Kingdom
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19
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Erenturk SA, Haciyakupoglu S, Senkal BF. Investigation of interaction behaviours of cesium and strontium ions with engineering barrier material to prevent leakage to environmental. J Environ Radioact 2020; 213:106101. [PMID: 31743850 DOI: 10.1016/j.jenvrad.2019.106101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 10/31/2019] [Accepted: 11/03/2019] [Indexed: 06/10/2023]
Abstract
This study deals with performance of removal of cesium (Cs+) and strontium (Sr2+) ions from synthetic aqueous solution using amino pyridine sulfone amid resin as a barrier material for nuclear waste storage areas to reduce environmental risk. The effects of adsorbate concentration, temperature and contact time on the efficiencies of the engineering barrier material for Cs+ and Sr2+ ions were investigated and evaluated. It was found that total adsorption capacity was higher for cesium ions than strontium ions. Dubinin-Radushkevich (D-R) isotherm model was well fitted to the adsorption data for both ions. The micropore capacity of the barrier material was found as 4.20 mg for strontium ions and 5.40 mg for cesium ions. ΔH values were indicated that the interaction process is exothermic for both ions. The positive value of entropy for both ions show that randomness at the solid-solution interface increased. Pseudo-second-order model was well fitted the kinetic data.
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Affiliation(s)
- S Akyil Erenturk
- Istanbul Technical University, Energy Institute, 34469, Maslak-Istanbul, Turkey.
| | - S Haciyakupoglu
- Istanbul Technical University, Energy Institute, 34469, Maslak-Istanbul, Turkey
| | - B F Senkal
- Faculty of Science and Letters, Istanbul Technical University, 34469, Maslak, Turkey
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20
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Simpson A, Clarkson A, Gardner S, Al Jebali R, Kaiser R, Mahon D, Roe J, Ryan M, Shearer C, Yang G. Muon tomography for the analysis of in-container vitrified products. Appl Radiat Isot 2020; 157:109033. [PMID: 32063328 DOI: 10.1016/j.apradiso.2019.109033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 10/13/2019] [Accepted: 12/27/2019] [Indexed: 11/18/2022]
Abstract
Alternate treatment routes for radioactive waste are a key research area for much of the nuclear industry, with potentially significant savings available through volume reduction of waste. Achieving this requires a full and demonstrable understanding of waste product behaviour. For this purpose, the UK's National Nuclear Laboratory (NNL) has been collaborating with the University of Glasgow and Lynkeos Technology to develop passive techniques for analysis of waste containers over a number of years. In this instance, novel muon tomographic techniques have been applied to the analysis of thermally treated nuclear waste surrogates as part of a project to build and deploy a first of a kind muon imaging system for nuclear waste. The system has been deployed at NNL's Central Laboratory, Cumbria, UK, to analyse products from a series of thermal treatment technology trials, funded by the Nuclear Decommissioning Authority (NDA) through the Direct Research Portfolio (DRP). Analysis of the waste products using this technique has proven the value of muon analysis in the development of waste management technologies, proving an ability to understand the homogeneity of products and direct further destructive testing. Results from three different thermal treatment trials are presented, with three different surrogate intermediate level waste (ILW) forms in each.
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Affiliation(s)
- Allan Simpson
- National Nuclear Laboratory, Central Laboratory, Sellafield, Seascale, Cumbria, CA20 1PG, UK.
| | - Anthony Clarkson
- Lynkeos Technology Ltd, University of Glasgow, No. 11 The Square, Glasgow, G12 8QQ, UK
| | - Simon Gardner
- Lynkeos Technology Ltd, University of Glasgow, No. 11 The Square, Glasgow, G12 8QQ, UK
| | | | - Ralf Kaiser
- Lynkeos Technology Ltd, University of Glasgow, No. 11 The Square, Glasgow, G12 8QQ, UK
| | - David Mahon
- Lynkeos Technology Ltd, University of Glasgow, No. 11 The Square, Glasgow, G12 8QQ, UK
| | - Julian Roe
- National Nuclear Laboratory, Central Laboratory, Sellafield, Seascale, Cumbria, CA20 1PG, UK
| | - Matthew Ryan
- National Nuclear Laboratory, Central Laboratory, Sellafield, Seascale, Cumbria, CA20 1PG, UK
| | - Craig Shearer
- National Nuclear Laboratory, Central Laboratory, Sellafield, Seascale, Cumbria, CA20 1PG, UK
| | - Guangliang Yang
- Lynkeos Technology Ltd, University of Glasgow, No. 11 The Square, Glasgow, G12 8QQ, UK
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21
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Page JS, Reynolds JG, Cooke GA, Wells BE. Large cemented gibbsite agglomerates in alkaline nuclear waste at the Hanford site and the impacts to remediation. J Hazard Mater 2020; 384:121318. [PMID: 31623999 DOI: 10.1016/j.jhazmat.2019.121318] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 09/14/2019] [Accepted: 09/24/2019] [Indexed: 06/10/2023]
Abstract
Recent work with the remediation of legacy alkaline nuclear waste has focused on nanometer and micrometer particle sizes, emphasizing how these small particles can impact efforts to treat the waste. Building upon this work, we present here findings that show very large particles (several centimeters in size) also exist in these waste which likewise play an important role in the remediation process. While large cemented gibbsite nodules have been periodically reported in acid soils in the literature, this study found similar large gibbsite agglomerates (7 cm in diameter) in alkaline nuclear waste, the first time that such large agglomerates have been identified in an alkaline environment. The morphology of the gibbsite in the agglomerates that were grown over more than 40 years of storage in the waste tank were similar to the much smaller agglomerates that have been reported in previous shorter term studies. Fluid dynamics calculations indicate that these cemented particles would be difficult to mobilize with standard jet slurry technologies, which is consistent with their persistence in the waste heel after jet sluicing of the tank.
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Affiliation(s)
- Jason S Page
- Washington River Protection Solutions, LLC, P.O. Box 850, Richland, WA, USA
| | - Jacob G Reynolds
- Washington River Protection Solutions, LLC, P.O. Box 850, Richland, WA, USA.
| | - Gary A Cooke
- Washington River Protection Solutions, LLC, P.O. Box 850, Richland, WA, USA
| | - Beric E Wells
- Pacific Northwest National Laboratory, P.O. Box 800, Richland, WA, USA
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22
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Paulillo A, Clift R, Dodds J, Milliken A, Palethorpe S, Lettieri P. Data supporting UCrad and CGM, two novel methodologies for radiological impacts in Life Cycle Assessment. Data Brief 2020; 28:104857. [PMID: 31867416 DOI: 10.1016/j.dib.2019.104857] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 11/12/2019] [Accepted: 11/13/2019] [Indexed: 11/24/2022] Open
Abstract
Radiological impacts are often disregarded in Life Cycle Assessment (LCA) due to the lack of a standard and comprehensive framework for including the impacts of radionuclides alongside other emissions from industrial processes. This data article is related to the research articles “Radiological Impacts in Life Cycle Assessment. Part I: General framework and two practical methodologies” [1] and “Radiological Impacts in Life Cycle Assessment. Part II: Comparison of Methodologies” [2], which introduced two practical methodologies for assessing the radiological impacts in LCA; these are UCrad and the Critical Group Methodology (CGM). This article reports the characterisation factors, for routine direct discharges and releases from nuclear waste disposed in a geological disposal facility, obtained from both methodologies. The article also reports the underlying data supporting the methodologies and the analysis carried out in the related research articles.
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23
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Gujar RB, Mohapatra PK, Verboom W. Two novel extraction chromatographic resins containing benzene-centered tripodal diglycolamide ligands: Actinide uptake, kinetic modeling and isotherm studies. J Chromatogr A 2019; 1598:58-66. [PMID: 30987785 DOI: 10.1016/j.chroma.2019.03.067] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 03/28/2019] [Accepted: 03/30/2019] [Indexed: 10/27/2022]
Abstract
Two novel extraction chromatographic resins (EC), termed as RL-1 and RL-2, were prepared by impregnating two benzene-centered tripodal iglycolamide ligands (Bz-T-DGA) containing different spacer groups where the ligands are termed as L-1 and L-2, respectively. They were employed for the uptake of actinide and fission product ions, viz. Am3+, Eu3+, UO22+, Np4+, Pu4+, Sr2+, and Cs+, from acidic feeds. Weight distribution coefficient (Kd) values were measured by the batch method and the loaded metal ions were back extracted using a 0.01 M EDTA solution at pH 4. Kinetic modeling of the sorption data of Am(III) on both resins suggested pseudo-second order rate kinetics with rate constants of 1.68 × 10-6 and 2.47 × 10-6 g/cpm.min for the resins containing L-1 and L-2, respectively. Sorption isotherm studies indicated the Langmuir monolayer chemisorption phenomenon with Eu(III) experimentally determined saturation uptake capacities of 6.02 ± 0.11 and 5.49 ± 0.14 mg per g of RL-1 and RL-2 resins, respectively. As the batch uptake study results appeared encouraging, column studies were also carried out using both resins. The resin reusability data indicated a marginal change in the Kd values for the RL-1 resin up to three repeat runs beyond which a steady decrease of the Kd value was seen. On the other hand, in the case of RL-2 a steady decrease in the Kd values was observed for three repeat runs beyond which there was marginal change.
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Affiliation(s)
- Rajesh B Gujar
- Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai, Trombay, 400 085, India
| | - Prasanta K Mohapatra
- Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai, Trombay, 400 085, India.
| | - Willem Verboom
- Laboratory of Molecular Nanofabrication, MESA(+)Institute for Nanotechnology, University of Twente, P. O. Box 217, 7500 AE Enschede, the Netherlands
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24
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Gilhula JC, Patterson JT, Williams NJ, Itani R, Taylor-Pashow KML, Abney CW. Peroxide-treated metal-organic framework templated adsorbents for remediation of high level nuclear waste. J Hazard Mater 2019; 365:306-311. [PMID: 30447638 DOI: 10.1016/j.jhazmat.2018.11.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 11/02/2018] [Accepted: 11/03/2018] [Indexed: 06/09/2023]
Abstract
Remediation of legacy nuclear waste is one of the greatest challenges faced by the US Department of Energy, with projected cleanup efforts requiring over five decades and hundreds of billions of dollars. New materials are necessary to accelerate waste processing, achieving time and financial savings. Herein we report a peroxide treatment to a Ti metal-organic framework (MOF) and related MOF-templated adsorbents. The resulting materials displayed exceptional affinity for Am(III), achieving distribution coefficients in excess of 105 mL/g, and out-performing state-of-the-art benchmarks monosodium titanate (MST) and peroxo-treated modified MST (mMST) for removal of 85Sr(II) and 239, 240Pu(IV) from legacy nuclear waste simulant.
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Affiliation(s)
- James C Gilhula
- Chemical Sciences Division, Oak Ridge National Laboratory. One Bethel Valley Road, Oak Ridge, TN, 37831, United States
| | - Jacob T Patterson
- Chemical Sciences Division, Oak Ridge National Laboratory. One Bethel Valley Road, Oak Ridge, TN, 37831, United States
| | - Neil J Williams
- Chemical Sciences Division, Oak Ridge National Laboratory. One Bethel Valley Road, Oak Ridge, TN, 37831, United States
| | - Ram Itani
- Chemical Sciences Division, Oak Ridge National Laboratory. One Bethel Valley Road, Oak Ridge, TN, 37831, United States
| | | | - Carter W Abney
- Chemical Sciences Division, Oak Ridge National Laboratory. One Bethel Valley Road, Oak Ridge, TN, 37831, United States
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Sierra Perler IC, Beer HF, Müth J, Kramer A. Dismantling of the DIORIT research reactor - Conditioning of activated graphite. J Environ Radioact 2019; 196:199-203. [PMID: 28822611 DOI: 10.1016/j.jenvrad.2017.07.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 05/12/2017] [Accepted: 07/26/2017] [Indexed: 06/07/2023]
Abstract
The research reactor DIORIT at the Paul Scherrer Institute was a natural uranium reactor moderated by D2O. It was put in operation in 1960 and finally shut down in August 1977. The dismantling project started in 1982 and could be successfully finished on September 11th, 2012. About 40 tons of activated reactor graphite had to be conditioned during the dismantling of this research reactor. The problem of conditioning of activated reactor graphite had not been solved so far worldwide. Therefore a conditioning method considering radiation protection and economic aspects had to be developed. As a result, the graphite was crushed to a particle size smaller than 5 mm and added as sand substitute to a specially developed grout. The produced graphite concrete was used as a matrix for embedding dismantling waste in containers. By conditioning the graphite conventionally, about 58.5 m3 (13 containers) of waste volume would have been generated. The new PSI invention resulted in no additional waste caused by graphite. Consequently, the resulting waste volume, as well as the costs, were substantially reduced.
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Affiliation(s)
| | | | - Joachim Müth
- Paul Scherrer Institute (PSI), 5232, Villigen PSI, Switzerland
| | - Andreas Kramer
- Paul Scherrer Institute (PSI), 5232, Villigen PSI, Switzerland
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Lawter AR, Garcia WL, Kukkadapu RK, Qafoku O, Bowden ME, Saslow SA, Qafoku NP. Technetium and iodine aqueous species immobilization and transformations in the presence of strong reductants and calcite-forming solutions: Remedial action implications. Sci Total Environ 2018; 636:588-595. [PMID: 29723831 DOI: 10.1016/j.scitotenv.2018.04.240] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 04/17/2018] [Accepted: 04/17/2018] [Indexed: 06/08/2023]
Abstract
At the Hanford Site in southeastern Washington, discharge of radionuclide laden liquid wastes resulted in vadose zone contamination, providing a continuous source of these contaminants to groundwater. The presence of multiple contaminants (i.e., 99Tc and 129I) increases the complexity of finding viable remediation technologies to sequester contaminants in situ and protect groundwater. Although previous studies have shown the efficiency of zero valent iron (ZVI) and sulfur modified iron (SMI) in reducing mobile Tc(VII) to immobile Tc(IV) and iodate incorporation into calcite, the coupled effects from simultaneously using these remedial technologies have not been previously studied. In this first-of-a-kind laboratory study, we used reductants (ZVI or SMI) and calcite-forming solutions to simultaneously remove aqueous Tc(VII) and iodate via reduction and incorporation, respectively. The results confirmed that Tc(VII) was rapidly removed from the aqueous phase via reduction to Tc(IV). Most of the aqueous iodate was transformed to iodide faster than incorporation into calcite occurred, and therefore the I remained in the aqueous phase. These results suggested that this remedial pathway is not efficient in immobilizing iodate when reductants are present. Other experiments suggested that iodate removal via calcite precipitation should occur prior to adding reductants for Tc(VII) removal. When microbes were included in the tests, there was no negative impact on the microbial population but changes in the makeup of the microbial community were observed. These microbial community changes may have an impact on remediation efforts in the long-term that could not be seen in a short-term study. The results underscore the importance of identifying interactions between natural attenuation pathways and remediation technologies that only target individual contaminants.
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Affiliation(s)
- Amanda R Lawter
- Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, Richland, WA 99352, United States.
| | - Whitney L Garcia
- Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, Richland, WA 99352, United States
| | - Ravi K Kukkadapu
- Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, Richland, WA 99352, United States
| | - Odeta Qafoku
- Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, Richland, WA 99352, United States
| | - Mark E Bowden
- Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, Richland, WA 99352, United States
| | - Sarah A Saslow
- Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, Richland, WA 99352, United States
| | - Nikolla P Qafoku
- Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, Richland, WA 99352, United States
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27
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Castro HA, Luca V, Bianchi HL. Study of plasma off-gas treatment from spent ion exchange resin pyrolysis. Environ Sci Pollut Res Int 2018; 25:21403-21410. [PMID: 28337628 DOI: 10.1007/s11356-017-8766-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 03/08/2017] [Indexed: 06/06/2023]
Abstract
Polystyrene divinylbenzene-based ion exchange resins are employed extensively within nuclear power plants (NPPs) and research reactors for purification and chemical control of the cooling water system. To maintain the highest possible water quality, the resins are regularly replaced as they become contaminated with a range of isotopes derived from compromised fuel elements as well as corrosion and activation products including 14C, 60Co, 90Sr, 129I, and 137Cs. Such spent resins constitute a major proportion (in volume terms) of the solid radioactive waste generated by the nuclear industry. Several treatment and conditioning techniques have been developed with a view toward reducing the spent resin volume and generating a stable waste product suitable for long-term storage and disposal. Between them, pyrolysis emerges as an attractive option. Previous work of our group suggests that the pyrolysis treatment of the resins at low temperatures between 300 and 350 °C resulted in a stable waste product with a significant volume reduction (>50%) and characteristics suitable for long-term storage and/or disposal. However, another important issue to take into account is the complexity of the off-gas generated during the process and the different technical alternatives for its conditioning. Ongoing work addresses the characterization of the ion exchange resin treatment's off-gas. Additionally, the application of plasma technology for the treatment of the off-gas current was studied as an alternative to more conventional processes utilizing oil- or gas-fired post-combustion chambers operating at temperatures in excess of 1000 °C. A laboratory-scale flow reactor, using inductively coupled plasma, operating under sub-atmospheric conditions was developed. Fundamental experiments using model compounds have been performed, demonstrating a high destruction and removal ratio (>99.99%) for different reaction media, at low reactor temperatures and moderate power consumption. The role of H2O as an important participant of the oxidation mechanisms in plasma conditions was established. The combination of both processes could represent a simple, safe, and effective alternative for treating spent ion exchange resins with a large reduction of generated gaseous byproducts in fuel cycle facilities where processes that utilize open flames are undesirable.
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Affiliation(s)
- Hernán Ariel Castro
- Programa Nacional de Gestión de Residuos Radiactivos, Comisión Nacional de Energía Atómica, Centro Atómico Constituyentes, Av. General Paz 1499, 1650, San Martín, Buenos Aires, Argentina
- Escuela de Ciencia y Tecnología, Universidad Nacional de General San Martín, Campus Miguelete, Martín de Irigoyen 3100, 1650, San Martín, Argentina
| | - Vittorio Luca
- Programa Nacional de Gestión de Residuos Radiactivos, Comisión Nacional de Energía Atómica, Centro Atómico Constituyentes, Av. General Paz 1499, 1650, San Martín, Buenos Aires, Argentina
| | - Hugo Luis Bianchi
- Escuela de Ciencia y Tecnología, Universidad Nacional de General San Martín, Campus Miguelete, Martín de Irigoyen 3100, 1650, San Martín, Argentina.
- Gerencia de Química, Comisión Nacional de Energía Atómica, Centro Atómico Constituyentes, Av. General Paz 1499, 1650, San Martín, Buenos Aires, Argentina.
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28
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Prăvălie R, Bandoc G. Nuclear energy: Between global electricity demand, worldwide decarbonisation imperativeness, and planetary environmental implications. J Environ Manage 2018; 209:81-92. [PMID: 29287177 DOI: 10.1016/j.jenvman.2017.12.043] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 11/30/2017] [Accepted: 12/17/2017] [Indexed: 05/26/2023]
Abstract
For decades, nuclear energy has been considered an important option for ensuring global energy security, and it has recently started being promoted as a solution for climate change mitigation. However, nuclear power remains highly controversial due to its associated risks - nuclear accidents and problematic radioactive waste management. This review aims to assess the viability of global nuclear energy economically (energy-wise), climatically and environmentally. To this end, the nuclear sector's energy- and climate-related advantages were explored alongside the downsides that mainly relate to radioactive pollution. Economically, it was found that nuclear energy is still an important power source in many countries around the world. Climatically, nuclear power is a low-carbon technology and can therefore be a viable option for the decarbonization of the world's major economies over the following decades, if coupled with other large-scale strategies such as renewable energies. These benefits are however outweighed by the radioactive danger associated to nuclear power plants, either in the context of the nuclear accidents that have already occurred or in that of the large amounts of long-lived nuclear waste that have been growing for decades and that represent a significant environmental and societal threat.
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Affiliation(s)
- Remus Prăvălie
- University of Bucharest, Faculty of Geography, Center for Coastal Research and Environmental Protection, 1 Nicolae Bălcescu Str., 010041, Bucharest, Romania.
| | - Georgeta Bandoc
- University of Bucharest, Faculty of Geography, Center for Coastal Research and Environmental Protection, 1 Nicolae Bălcescu Str., 010041, Bucharest, Romania.
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29
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Zhang ZF, Strickland CE, Link SO. Design and performance evaluation of a 1000-year evapotranspiration-capillary surface barrier. J Environ Manage 2017; 187:31-42. [PMID: 27870996 DOI: 10.1016/j.jenvman.2016.11.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 10/13/2016] [Accepted: 11/05/2016] [Indexed: 06/06/2023]
Abstract
Surface barrier technology is used to isolate radioactive waste and to reduce or eliminate recharge water to the waste zone for 1000 years or longer. However, the design and evaluation of such a barrier is challenging because of the extremely long design life. After establishing a set of design and performance objectives, a package of design solutions was developed for 1000-year surface barriers over nuclear waste sites. The Prototype Hanford Barrier (PHB) was then constructed in 1994 in the field over an existing waste site as a demonstration. The barrier was tested to evaluate surface-barrier design and performance at the field scale under conditions of enhanced and natural precipitation and of no vegetation. The monitoring data demonstrate that the barrier satisfied nearly all objectives in the past two decades. The PHB far exceeded the Resource Conservation and Recovery Act criteria, functioned in Hanford's semiarid climate, limited drainage to well below the 0.5 mm yr-1 performance criterion, limited runoff, and minimized erosion and bio-intrusion. Given the two-decade record of successful performance and consideration of the processes and mechanisms that could affect barrier stability and hydrology in the future, the results suggest the PHB is very likely to perform for its 1000-year design life. This conclusion is based on two assumptions: (1) the exposed subgrade receives protection against erosion and (2) institutional controls prevent inadvertent human activity at the barrier. The PHB design can serve as the basis for site-specific barriers over waste sites containing underground nuclear waste, uranium mine tailings, and hazardous mine waste.
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Affiliation(s)
- Zhuanfang Fred Zhang
- Hydrology Group, Earth Systems Science Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
| | - Christopher E Strickland
- Hydrology Group, Earth Systems Science Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Steven O Link
- Energy and Environmental Science Program, Department of Natural Resources, Confederated Tribes of the Umatilla Indian Reservation, 46411 Timine Way, Pendleton, OR 97801, USA
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30
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Poirot-Delpech S, Raineau L. Nuclear Waste Facing the Test of Time: The Case of the French Deep Geological Repository Project. Sci Eng Ethics 2016; 22:1813-1830. [PMID: 26679349 DOI: 10.1007/s11948-015-9739-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 12/01/2015] [Indexed: 06/05/2023]
Abstract
The purpose of this article is to consider the socio-anthropological issues raised by the deep geological repository project for high-level, long-lived nuclear waste. It is based on fieldwork at a candidate site for a deep storage project in eastern France, where an underground laboratory has been studying the feasibility of the project since 1999. A project of this nature, based on the possibility of very long containment (hundreds of thousands of years, if not longer), involves a singular form of time. By linking project performance to geology's very long timescale, the project attempts "jump" in time, focusing on a far distant future, without understanding it in terms of generations. But these future generations remain measurements of time on the surface, where the issue of remembering or forgetting the repository comes to the fore. The nuclear waste geological storage project raises questions that neither politicians nor scientists, nor civil society, have ever confronted before. This project attempts to address a problem that exists on a very long timescale, which involves our responsibility toward generations in the far future.
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Affiliation(s)
- Sophie Poirot-Delpech
- CETCOPRA (Centre d'étude des techniques, des connaissances et des pratiques), Paris 1 Panthéon-Sorbonne University, Paris, France
| | - Laurence Raineau
- CETCOPRA (Centre d'étude des techniques, des connaissances et des pratiques), Paris 1 Panthéon-Sorbonne University, Paris, France.
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Abstract
The current situation and possible future developments for nuclear power--including fission and fusion processes--is presented. The fission nuclear power continues to be an essential part of the low-carbon electricity generation in the world for decades to come. There are breakthrough possibilities in the development of new generation nuclear reactors where the life-time of the nuclear waste can be reduced to some hundreds of years instead of the present time-scales of hundred thousand of years. Research on the fourth generation reactors is needed for the realisation of this development. For the fast nuclear reactors, a substantial research and development effort is required in many fields--from material sciences to safety demonstration--to attain the envisaged goals. Fusion provides a long-term vision for an efficient energy production. The fusion option for a nuclear reactor for efficient production of electricity has been set out in a focussed European programme including the international project of ITER after which a fusion electricity DEMO reactor is envisaged.
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Affiliation(s)
- Akos Horvath
- MTA Centre for Energy Research, KFKI Campus, P.O.B. 49, Budapest 114, 1525, Hungary.
| | - Elisabeth Rachlew
- Department of Physics, Royal Institute of Technology, KTH, 10691, Stockholm, Sweden.
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32
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Gueroult R, Hobbs DT, Fisch NJ. Plasma filtering techniques for nuclear waste remediation. J Hazard Mater 2015; 297:153-159. [PMID: 25956646 DOI: 10.1016/j.jhazmat.2015.04.058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 04/20/2015] [Accepted: 04/20/2015] [Indexed: 06/04/2023]
Abstract
Nuclear waste cleanup is challenged by the handling of feed stocks that are both unknown and complex. Plasma filtering, operating on dissociated elements, offers advantages over chemical methods in processing such wastes. The costs incurred by plasma mass filtering for nuclear waste pretreatment, before ultimate disposal, are similar to those for chemical pretreatment. However, significant savings might be achieved in minimizing the waste mass. This advantage may be realized over a large range of chemical waste compositions, thereby addressing the heterogeneity of legacy nuclear waste.
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Affiliation(s)
- Renaud Gueroult
- Princeton Plasma Physics Laboratory, Princeton, NJ 08540, USA.
| | - David T Hobbs
- Savannah River National Laboratory, Aiken, SC 29808, USA
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33
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Miller A, Kruichak J, Mills M, Wang Y. Iodide uptake by negatively charged clay interlayers? J Environ Radioact 2015; 147:108-114. [PMID: 26057987 DOI: 10.1016/j.jenvrad.2015.05.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 05/21/2015] [Accepted: 05/26/2015] [Indexed: 06/04/2023]
Abstract
Understanding iodide interactions with clay minerals is critical to quantifying risk associated with nuclear waste disposal. Current thought assumes that iodide does not interact directly with clay minerals due to electrical repulsion between the iodide and the negatively charged clay layers. However, a growing body of work indicates a weak interaction between iodide and clays. The goal of this contribution is to report a conceptual model for iodide interaction with clays by considering clay mineral structures and emergent behaviors of chemical species in confined spaces. To approach the problem, a suite of clay minerals was used with varying degrees of isomorphic substitution, chemical composition, and mineral structure. Iodide uptake experiments were completed with each of these minerals in a range of swamping electrolyte identities (NaCl, NaBr, KCl) and concentrations. Iodide uptake behaviors form distinct trends with cation exchange capacity and mineral structure. These trends change substantially with electrolyte composition and concentration, but do not appear to be affected by solution pH. The experimental results suggest that iodide may directly interact with clays by forming ion-pairs (e.g., NaI(aq)) which may concentrate within the interlayer space as well as the thin areas surrounding the clay particle where water behavior is more structured relative to bulk water. Ion pairing and iodide concentration in these zones is probably driven by the reduced dielectric constant of water in confined space and by the relatively high polarizability of the iodide species.
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Affiliation(s)
- Andrew Miller
- Emporia State University, 1 Kellogg Circle, Emporia, KS, 66801, United States.
| | - Jessica Kruichak
- Sandia National Laboratories, 1515 Eubank SE, Albuquerque, NM, 87185-0779, United States
| | - Melissa Mills
- Sandia National Laboratories, 1515 Eubank SE, Albuquerque, NM, 87185-0779, United States
| | - Yifeng Wang
- Sandia National Laboratories, 1515 Eubank SE, Albuquerque, NM, 87185-0779, United States
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34
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Lusa M, Bomberg M, Aromaa H, Knuutinen J, Lehto J. The microbial impact on the sorption behaviour of selenite in an acidic, nutrient-poor boreal bog. J Environ Radioact 2015; 147:85-96. [PMID: 26048060 DOI: 10.1016/j.jenvrad.2015.05.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 05/12/2015] [Accepted: 05/13/2015] [Indexed: 06/04/2023]
Abstract
(79)Se is among the most important long lived radionuclides in spent nuclear fuel and selenite, SeO3(2-), is its typical form in intermediate redox potential. The sorption behaviour of selenite and the bacterial impact on the selenite sorption in a 7-m-deep profile of a nutrient-poor boreal bog was studied using batch sorption experiments. The batch distribution coefficient (Kd) values of selenite decreased as a function of sampling depth and highest Kd values, 6600 L/kg dry weight (DW), were observed in the surface moss and the lowest in the bottom clay at 1700 L/kg DW. The overall maximum sorption was observed at pH between 3 and 4 and the Kd values were significantly higher in unsterilized compared to sterilized samples. The removal of selenite from solution by Pseudomonas sp., Burkholderia sp., Rhodococcus sp. and Paenibacillus sp. strains isolated from the bog was affected by incubation temperature and time. In addition, the incubation of sterilized surface moss, subsurface peat and gyttja samples with added bacteria effectively removed selenite from the solution and on average 65% of selenite was removed when Pseudomonas sp. or Burkholderia sp. strains were used. Our results demonstrate the important role of bacteria for the removal of selenite from the solution phase in the bog environment, having a high organic matter content and a low pH.
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Affiliation(s)
- M Lusa
- Laboratory of Radiochemistry, Department of Chemistry, P.O. Box 55, 00014 University of Helsinki, Finland.
| | - M Bomberg
- VTT Technical Research Centre of Finland, P.O. Box 1000, 02044 VTT, Finland
| | - H Aromaa
- Laboratory of Radiochemistry, Department of Chemistry, P.O. Box 55, 00014 University of Helsinki, Finland
| | - J Knuutinen
- Laboratory of Radiochemistry, Department of Chemistry, P.O. Box 55, 00014 University of Helsinki, Finland
| | - J Lehto
- Laboratory of Radiochemistry, Department of Chemistry, P.O. Box 55, 00014 University of Helsinki, Finland
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Doroshenko I, Zurkova J, Moravec Z, Bezdicka P, Pinkas J. Sonochemical precipitation of amorphous uranium phosphates from trialkyl phosphate solutions and their thermal conversion to UP2O7. Ultrason Sonochem 2015; 26:157-162. [PMID: 25640684 DOI: 10.1016/j.ultsonch.2015.01.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 12/29/2014] [Accepted: 01/19/2015] [Indexed: 05/27/2023]
Abstract
Insoluble amorphous precipitates containing uranyl and phosphate ions are obtained by sonication of solutions of three uranyl precursors, UO2(X)2, X=NO3, CH3COO, CH3C(O)CHC(O)CH3 (acetylacetonate, acac), in triesters of phosphoric acid, OP(OR)3, R=Me (trimethyl phosphate, TMP), Et (triethyl phosphate, TEP). TMP and TEP are used as high-boiling solvents and they serve also as a source of phosphate anions. Sonolysis experiments were carried out under flow of Ar at 40°C on a Sonics and Materials VXC 500W system (f=20 kHz, Pac=0.49 W cm(-3)). Powder X-ray diffraction (PXRD) reveals amorphous character of all obtained precipitates. The presence of uranyl and phosphate is evidenced by IR spectroscopy and ICP-OES analysis reveals the content of both U (38.6-43.4 wt%) and P (11.0-13.6 wt%). The thermal behavior of the substances was studied by TG/DSC analysis, which shows weight losses in the range of 19.21-24.08%. On heating the amorphous precipitates to 1000°C, crystalline uranium diphosphate UP2O7 is obtained in all cases as the only crystalline phase. Uranyl(VI) is reduced during thermolysis to U(IV) as there is no characteristic vibration of UO2(2+) in the IR spectra of solid UP2O7 products. The ICP-OES analysis of U and P content in precipitates allowed us to calculate the efficiency of precipitation of uranium from mother liquor and to compare it with the efficiency calculated from the data received by the PXRD and TG/DSC analyses. The efficiency of the uranium removal attained by our sonoprecipitation procedure was typically 30-35%. These sonochemical precipitation reactions providing insoluble uranium phosphates may be potentially interesting models for the description of behavior of uranium-containing waste or reprocessing streams.
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Affiliation(s)
- Iaroslav Doroshenko
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic; Central European Institute of Technology (CEITEC), Masaryk University, CZ-62500 Brno, Czech Republic
| | - Jana Zurkova
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic
| | - Zdenek Moravec
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic
| | - Petr Bezdicka
- Institute of Inorganic Chemistry ASCR, CZ-25068 Rez, Czech Republic
| | - Jiri Pinkas
- Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, CZ-61137 Brno, Czech Republic; Central European Institute of Technology (CEITEC), Masaryk University, CZ-62500 Brno, Czech Republic.
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Paraneeiswaran A, Shukla SK, Prashanth K, Rao TS. Microbial reduction of [Co(III)-EDTA]⁻ by Bacillus licheniformis SPB-2 strain isolated from a solar salt pan. J Hazard Mater 2014; 283:582-590. [PMID: 25464299 DOI: 10.1016/j.jhazmat.2014.09.058] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 09/15/2014] [Accepted: 09/23/2014] [Indexed: 06/04/2023]
Abstract
Naturally stressed habitats are known to be repositories for novel microorganisms with potential bioremediation applications. In this study, we isolated a [Co(III)-EDTA](-) reducing bacterium Bacillus licheniformis SPB-2 from a solar salt pan that is exposed to constant cycles of hydration and desiccation in nature. [Co(III)-EDTA](-) generated during nuclear waste management process is difficult to remove from the waste due to its high stability and solubility. It is reduced form i.e. [Co(II)-EDTA](2-) is less stable though it is toxic. This study showed that B. licheniformis SPB-2 reduced 1mM [Co(III)-EDTA](-) in 14 days when grown in a batch mode. However, subsequent cycles showed an increase in the reduction activity, which was observed up to four cycles. Interestingly, the present study also showed that [Co(III)-EDTA](-) acted as an inducer for B. licheniformis SPB-2 spore germination. Vegetative cells germinated from the spores were found to be involved in [Co(III)-EDTA](-) reduction. More detailed investigations showed that after [Co(III)-EDTA](-) reduction, i.e. [Co(II)-EDTA](2-) complex was removed by B. licheniformis SPB-2 from the bulk liquid by adsorption phenomenon. The bacterium showed a D10 value (radiation dose required to kill 90% cells) of ∼250 Gray (Gy), which signifies the potential use of B. licheniformis SPB-2 for bioremediation of moderately active nuclear waste.
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Affiliation(s)
| | - Sudhir K Shukla
- Biofouling & Biofilm Processes Section, Water & Steam Chemistry Division, BARC Facilities, Kalpakkam 603102, India; Homi Bhabha National Institute, Mumbai 400094, India
| | - K Prashanth
- Departartment of Biotechnology, Pondicherry University, Puducherry, India
| | - T Subba Rao
- Biofouling & Biofilm Processes Section, Water & Steam Chemistry Division, BARC Facilities, Kalpakkam 603102, India; Homi Bhabha National Institute, Mumbai 400094, India.
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Reynolds JG, Huber HJ, Cooke GA, Pestovich JA. Solid-phase zirconium and fluoride species in alkaline zircaloy cladding waste at Hanford. J Hazard Mater 2014; 278:203-210. [PMID: 24976128 DOI: 10.1016/j.jhazmat.2014.05.097] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 05/27/2014] [Accepted: 05/31/2014] [Indexed: 06/03/2023]
Abstract
The United States Department of Energy Hanford Site, near Richland, Washington, USA, processed plutonium between 1944 and 1987. Fifty-six million gallons of waste of various origins remain, including waste from removing zircaloy fuel cladding using the so-called Zirflex process. The speciation of zirconium and fluoride in this waste is important because of the corrosivity and reactivity of fluoride as well as the (potentially) high density of Zr-phases. This study evaluates the solid-phase speciation of zirconium and fluoride using X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). Two waste samples were analyzed: one waste sample that is relatively pure zirconium cladding waste from tank 241-AW-105 and another that is a blend of zirconium cladding wastes and other high-level wastes from tank 241-C-104. Villiaumite (NaF) was found to be the dominant fluoride species in the cladding waste and natrophosphate (Na7F[PO4]2 · 19H2O) was the dominant species in the blended waste. Most zirconium was present as a sub-micron amorphous Na-Zr-O phase in the cladding waste and a Na-Al-Zr-O phase in the blended waste. Some zirconium was present in both tanks as either rounded or elongated crystalline needles of Na-bearing ZrO2 that are up to 200 μm in length. These results provide waste process planners the speciation data needed to develop disposal processes for this waste.
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Affiliation(s)
- Jacob G Reynolds
- Washington River Protection Solutions, LLC, P.O. Box 850, MSIN H6-04, Richland, WA 99352, USA.
| | - Heinz J Huber
- Washington River Protection Solutions, LLC, P.O. Box 850, MSIN H6-04, Richland, WA 99352, USA.
| | - Gary A Cooke
- Washington River Protection Solutions, LLC, P.O. Box 850, MSIN H6-04, Richland, WA 99352, USA.
| | - John A Pestovich
- Washington River Protection Solutions, LLC, P.O. Box 850, MSIN H6-04, Richland, WA 99352, USA.
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Perko T. Radiation risk perception: a discrepancy between the experts and the general population. J Environ Radioact 2014; 133:86-91. [PMID: 23683940 DOI: 10.1016/j.jenvrad.2013.04.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 04/07/2013] [Accepted: 04/13/2013] [Indexed: 05/16/2023]
Abstract
Determining the differences in the perception of risks between experts who are regularly exposed to radiation, and lay people provides important insights into how potential hazards may be effectively communicated to the public. In the present study we examined lay people's (N = 1020) and experts' (N = 332) perception of five different radiological risks: nuclear waste, medical x-rays, natural radiation, an accident at a nuclear installation in general, and the Fukushima accident in particular. In order to link risk perception with risk communication, media reporting about radiation risks is analysed using quantitative and qualitative content analyses. The results showed that experts perceive radiological risks differently from the general public. Experts' perception of medical X-rays and natural radiation is significantly higher than in general population, while for nuclear waste and an accident at a nuclear installation, experts have lower risk perception than the general population. In-depth research is conducted for a group of workers that received an effective dose higher than 0.5 mSv in the year before the study; for this group we identify predictors of risk perception. The results clearly show that mass media don't use the same language as technical experts in addressing radiological risks. The study demonstrates that the discrepancy in risk perception and the communication gap between the experts and the general population presents a big challenge in understanding each other.
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Affiliation(s)
- Tanja Perko
- Belgian Nuclear Research Centre SCK CEN, Boeretang 200, B-2400 Mol, Belgium.
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Bartoś B, Filipowicz B, Łyczko M, Bilewicz A. Adsorption of 137Cs on titanium ferrocyanide and transformation of the sorbent to lithium titanate: a new method for long term immobilization of 137Cs. J Radioanal Nucl Chem 2014; 302:513-6. [PMID: 26224978 DOI: 10.1007/s10967-014-3218-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Dynamic adsorption of radiocesium on titanium ferrocyanide grains from reactor coolant simulating solution containing salts at moderate concentrations has been investigated. Effective decontamination of the neutral solutions has been achieved, in the amounts of a more than 20 thousand bed volumes. After adsorption the titanium ferrocyanide was transferred to titanates and calcined at 900 °C. The leaching test of the obtained lithium titanates indicates that the loaded adsorbent can serve as an effective primary barrier in nuclear waste repositories.
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Hormann V, Fischer HW. Estimating the distribution of radionuclides in agricultural soils - dependence on soil parameters. J Environ Radioact 2013; 124:278-286. [PMID: 23871968 DOI: 10.1016/j.jenvrad.2013.06.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 05/21/2013] [Accepted: 06/14/2013] [Indexed: 06/02/2023]
Abstract
In this study it is shown how radionuclide distributions in agricultural soils and their dependence on soil parameters can be quantitatively estimated. The most important sorption and speciation processes have been implemented into a numerical model using the geochemical code PHREEQC that is able to include specific soil and soil solution compositions. Using this model, distribution coefficients (Kd values) for the elements Cs, Ni, U and Se have been calculated for two different soil types. Furthermore, the dependencies of these Kd values on various soil parameters (e.g. pH value or organic matter content) have been evaluated. It is shown that for each element, an individual set of soil parameters is relevant for its solid-liquid distribution. The model may be used for the calculation of input parameters used by reference biosphere models (e.g. used for the risk assessment of nuclear waste repositories).
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Affiliation(s)
- Volker Hormann
- University of Bremen, Institute of Environmental Physics, Otto-Hahn-Allee 1, D-28359 Bremen, Germany.
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