Americium separations from high-salt solutions using anion exchange

Citation
Me. Barr et al., Americium separations from high-salt solutions using anion exchange, SEP SCI TEC, 36(12), 2001, pp. 2609-2622
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemistry
Journal title
SEPARATION SCIENCE AND TECHNOLOGY
ISSN journal
0149-6395 → ACNP
Volume
36
Issue
12
Year of publication
2001
Pages
2609 - 2622
Database
ISI
SICI code
0149-6395(2001)36:12<2609:ASFHSU>2.0.ZU;2-K
Abstract
The aging of the US nuclear stockpile presents a number of challenges, incl uding the increasing radioactivity of plutonium residues due to the in grow th of Am-241 from the beta -decay of Pu-241. We investigated parameters tha t affect the sorption of Am onto anion-exchange resins from concentrated ef fluents derived from nitric acid processing of plutonium residues. These po stevaporator wastes are nearly saturated solutions of acidic nitrate salts, and americium removal is complicated by physical factors, such as solution viscosity and particulates, as well as by the presence of large quantities of competing metals and acid. Single- and double-contact batch distributio n coefficients for americium and neodymium from simple and complex surrogat e solutions are presented. Varied parameters include the nitrate salt conce ntration and composition and the nitric acid concentration. We find that un der these extremely concentrated conditions, Am(III) removal efficiencies c an surpass 50% per contact. Distribution coefficients for both neodymium. a nd americium are insensitive to solution acidity and appear to be driven pr imarily by low water activities of the solutions.