Determination of 239Pu in fluoride target sample material with MILEA AMS

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21340%2F22%3A00361911" target="_blank" >RIV/68407700:21340/22:00361911 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Determination of 239Pu in fluoride target sample material with MILEA AMS

Original language description

Accelerator mass spectrometry (AMS) is a very sensitive analytical method for determination of ultra-trace concentrations of long-lived radionuclides in environmental samples. In compare with others method AMS enables to measure isotopic ratios by detecting the atoms. In practice is from the 239/240Pu ratio possible to identify the origin of distribution of plutonium in the environment, if it is a consequence from global fallout or from releases from nuclear facilities. Pu-239 is an anthropogenic alpha emitter with the half-life of 24 000 years. Plutonium fluoride matrices based on lanthanide co-precipitation have been tested similarly as uranium fluorides as new potential target materials in previous studies [1]. Compared to commonly used oxides, fluoride potential target materials of plutonium can suppress isobaric interferences and provides significantly more intense beams and higher ionization yield values over shorter time periods [2]. The preparation of the fluoride matrix is based on co-precipitation of plutonium from hydrochloric or nitric acid solutions by adding praseodymium chloride and hydrofluoric acid. After washing and drying the material is mixed with lead fluoride to increase the extracted ion currents [3]. The oxide material was prepared with the plutonium incorporation into iron oxide and after annealing it was mixed with niobium powder. The chemical analysis of prepared plutonium-fluoride and oxides materials confirmed successful incorporation of plutonium into PrF3 with co-precipitation yield over 99%. The aim of the research is to evaluate the performance of prepared plutonium fluoride matrices with the MILEA AMS, 300kV accelerator system at ETH Zürich. The measurements included tuning the system for 239Pu determination using fluoride and oxides target samples, background analyses of both target matrices, focusing on the 238U interference, and the ionization efficiency tests for plutonium extracted from both matrices in the form of PuF4-, PuF5- and PuO-. The background from U-238 was investigated by doping selected samples with different amounts of U-238, which allowes a direct comparison of the influence of the different matrices on the background. [1] Kazi Z. H. et al.: Comparison of the measurement of Pu and Am isotopes by AMS using fluoride and oxide anion beams, J. Anal. At. Spectrom., (2015) [2] Cornett R. J. et al., NIMB 361 (2015) 317 [3] Zhao, X.-L. et al., Studies of anions from sputtering I: Survey of MFn-. NIMB 268. 807-811(2010)

Czech name

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Czech description

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Type

O - Miscellaneous

CEP classification

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OECD FORD branch

21100 - Other engineering and technologies

Project

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Continuities

S - Specificky vyzkum na vysokych skolach

Publication year

2022

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů