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Surman J.J.,Lancaster University | Pates J.M.,Lancaster University | Zhang H.,Lancaster University | Happel S.,Triskem International
Talanta | Year: 2014

A new resin selective for Sr has been developed and characterised for the direct binding of 90Sr from environmental waters with minimal pre-treatment. The new selective resin comprises of a mixture of two extractants, 4,4′(5′)-bis-t-butylcyclohexano-18-crown-6 and di(2-ethyl-hexyl)phosphoric acid, sorbed onto Amberchrom CG-71. Sr uptake is shown to be high (the distribution weight coefficient Dw >100 mL g-1) across a range of environmentally realistic conditions (pH 2-8 and up to 11,500 mg L-1 NaCl, 500 mg L-1 Ca, 400 mg L -1 K and 1300 mg L-1 Mg). The Sr capacity of the resin is shown to be 7.7±0.4 mg g-1, meaning that the resin has a sufficient capacity to quantitatively remove Sr from most environmental water samples. The reasonably fast uptake kinetics of the resin (95±4% of strontium bound within 30 min) results in a resin that is applicable to both batch- and column-type separation procedures. A range of potentially co-extracted radio-elements have been identified and an elution scheme has been developed to separate interferences, including 90Y, from 90Sr. The clean elution of 90Sr permits immediate measurement by radiometric means, with no need for complicated spectral processing or waiting for secular equilibrium between 90Sr and 90Y. The characterised resin is applicable for use in rapid determination procedures, enabling the swift analysis of water samples required by monitoring schemes at contaminated nuclear sites and in the aftermath of nuclear accidents. © 2014 Elsevier B.V. Source


Decamp C.,Institute des Radioelements IRE | Happel S.,Triskem International
Journal of Radioanalytical and Nuclear Chemistry | Year: 2013

Safety and appropriate management of nuclear waste are of major importance in radioisotope production. Radioiodine has been identified as one of the most dangerous radioelements in terms of radiological effects in case of accidental release; accordingly substantial efforts are made to optimize the iodine capture in liquid effluents to avoid any possible iodine gas release from liquid waste during storage. The IRE (National Institute for Radioelements) produces radioelements such as Mo-99 for nuclear medicine. Its production process results in highly acidic and oxidizing effluents containing iodine which might thus be present in various oxidation states and species. This needs to be taken into account for the development of a decontamination process for these effluents. CL Resin (TrisKem International) is an extraction chromatographic resin showing high selectivity for noble metals over a large number of other elements. The CL Resin retains silver over a wide pH range including high acid concentrations. It was further shown, after being loaded with silver, to strongly retain iodine species forming insoluble complexes with silver making it well suited for use in the given context; XAD-4 Resin (Sigma-Aldrich) on the other hand is known to retain elemental iodine. A mixed bed column based on silver loaded CL Resin and XAD-4 resin was developed and optimized for iodine removal from IRE's process effluents. Prepared mixed bed columns were evaluated by treating multi-curies production process solutions at the IRE. These columns showed high iodine removal from elevated effluent volumes (>10 L) even at flow-rates up to >180 mL min-1. © 2013 Akadémiai Kiadó, Budapest, Hungary. Source


Calmet D.,French Atomic Energy Commission | Ameon R.,Institute for Radiological Protection and Nuclear Safety | Bombard A.,Triskem International | Forte M.,Centro Regionale Of Radioprotezione | And 6 more authors.
Applied Radiation and Isotopes | Year: 2013

Water is vital to humans and each of us needs at least 1.5. L of safe water a day to drink. Beginning as long ago as 1958 the World Health Organization (WHO) has published guidelines to help ensure water is safe to drink. Focused from the start on monitoring radionuclides in water, and continually cooperating with WHO, the International Standardization Organization (ISO) has been publishing standards on radioactivity test methods since 1978. As reliable, comparable and 'fit for purpose' results are an essential requirement for any public health decision based on radioactivity measurements, international standards of tested and validated radionuclide test methods are an important tool for production of such measurements.This paper presents the ISO standards already published that could be used as normative references by testing laboratories in charge of radioactivity monitoring of drinking water as well as those currently under drafting and the prospect of standardized fast test methods in response to a nuclear accident. © 2013 Elsevier Ltd. Source


Calmet D.,French Atomic Energy Commission | Ameon R.,Institute for Radiological Protection and Nuclear Safety | Beck T.,Federal office for Radiation Protection | Bombard A.,Triskem International | And 17 more authors.
Radiation Protection Dosimetry | Year: 2011

Radon is considered to be the main source of human exposure to natural radiation. As stated by the World Health Organization, the exposure due to the inhalation of indoor radon is much greater than the one via the ingestion of water as radon degasses from water during handling. In response to these concerns about the universal presence of radon, environmental assessment studies are regularly commissioned to assess the radon exposure of public and workers. The credibility of such studies relies on the quality and reliability of radon analysis as well as on the sample representativeness of the radiological situation. The standard-setting approach, based on consensus, seemed to lend itself to a settlement of technical aspects of potential comparison. At present, two Working Groups of the International Standardization Organization are focussing on drafting standards on radon and its decay products measurement in air and water. These standards, which aim for a set of rigorous metrology practices, will be useful for persons in charge of the initial characterisation of a site with respect to natural radioactivity as well as to those performing the routine surveillance of specific sites. © The Author 2011. Published by Oxford University Press. All rights reserved. Source


Gharibyan N.,University of Nevada, Las Vegas | Dailey A.,University of Nevada, Las Vegas | McLain D.R.,University of Nevada, Las Vegas | Bond E.M.,Los Alamos National Laboratory | And 3 more authors.
Solvent Extraction and Ion Exchange | Year: 2014

Due to the similar chemical properties between the neighboring trivalent actinide elements americium and curium, their extraction behavior is often perceived as indistinguishable. In this work, the characterization of seven extraction chromatography resins (TEVA, TRU, DGA(N), Actinide, Ln, Ln2, and Ln3) for these trivalent actinides from acidic matrices (HNO3, HCl, and HBr) has provided some evidence to the contrary. In most cases, Am(III) and Cm(III) exhibit identical extraction properties. However, separation is possible with TRU and DGA(N) resins as demonstrated in this study. The extraction shows a strong dependency on the specific anion in solution that follows the order NO3 ->Br->Cl-. Copyright © Taylor & Francis Group, LLC. Source

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