In:
Radiochimica Acta, Walter de Gruyter GmbH, Vol. 108, No. 2 ( 2020-01-28), p. 87-97
Abstract:
A radiochemical method for producing 82 Se sources with an ultra-low level of contamination of natural radionuclides ( 40 K, decay products of 232 Th and 238 U) has been developed based on cation-exchange chromatographic purification with reverse removal of impurities. It includes chromatographic separation (purification), reduction, conditioning (which includes decantation, centrifugation, washing, grinding, and drying), and 82 Se foil production. The conditioning stage, during which highly dispersed elemental selenium is obtained by the reduction of purified selenious acid (H 2 SeO 3 ) with sulfur dioxide (SO 2 ) represents the crucial step in the preparation of radiopure 82 Se samples. The natural selenium (600 g) was first produced in this procedure in order to refine the method. The technique developed was then used to produce 2.5 kg of radiopure enriched selenium ( 82 Se). The produced 82 Se samples were wrapped in polyethylene (12 μm thick) and radionuclides present in the sample were analyzed with the BiPo-3 detector. The radiopurity of the plastic materials (chromatographic column material and polypropylene chemical vessels), which were used at all stages, was determined by instrumental neutron activation analysis. The radiopurity of the 82 Se foils was checked by measurements with the BiPo-3 spectrometer, which confirmed the high purity of the final product. The measured contamination level for 208 Tl was 8–54 μBq/kg, and for 214 Bi the detection limit of 600 μBq/kg has been reached.
Type of Medium:
Online Resource
ISSN:
2193-3405
,
0033-8230
DOI:
10.1515/ract-2019-3129
Language:
English
Publisher:
Walter de Gruyter GmbH
Publication Date:
2020
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