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Title: Advancing the scientific basis of trivalent actinide-lanthanide separations

Abstract

For advanced fuel cycles designed to support transmutation of transplutonium actinides, several options have been demonstrated for process-scale aqueous separations for U, Np, Pu management and for partitioning of trivalent actinides and fission product lanthanides away from other fission products. The more difficult mutual separation of Am/Cm from La-Tb remains the subject of considerable fundamental and applied research. The chemical separations literature teaches that the most productive alternatives to pursue are those based on ligand donor atoms less electronegative than O, specifically N- and S-containing complexants and chloride ion (Cl{sup -}). These 'soft-donor' atoms have exhibited usable selectivity in their bonding interactions with trivalent actinides relative to lanthanides. In this report, selected features of soft donor reagent design, characterization and application development will be discussed. The roles of thiocyanate, aminopoly-carboxylic acids and lactate in separation processes are detailed. (authors)

Authors:
 [1]
  1. Washington State University, Department of Chemistry, PO Box 644630, Pullman, WA 99164-4630 (United States)
Publication Date:
Research Org.:
American Nuclear Society, 555 North Kensington Avenue, La Grange Park, IL 60526 (United States)
OSTI Identifier:
22264127
Resource Type:
Conference
Resource Relation:
Conference: GLOBAL 2013: International Nuclear Fuel Cycle Conference - Nuclear Energy at a Crossroads, Salt Lake City, UT (United States), 29 Sep - 3 Oct 2013; Other Information: Country of input: France; 25 refs.; Related Information: In: Proceedings of GLOBAL 2013: International Nuclear Fuel Cycle Conference - Nuclear Energy at a Crossroads| 1633 p.
Country of Publication:
United States
Language:
English
Subject:
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; ACTINIDES; BONDING; CARBOXYLIC ACIDS; CHLORINE IONS; FISSION PRODUCTS; FUEL CYCLE; LACTATES; LIGANDS; NUCLEAR FUELS; RARE EARTHS; SEPARATION PROCESSES; THIOCYANATES

Citation Formats

Nash, K.L. Advancing the scientific basis of trivalent actinide-lanthanide separations. United States: N. p., 2013. Web.
Nash, K.L. Advancing the scientific basis of trivalent actinide-lanthanide separations. United States.
Nash, K.L. 2013. "Advancing the scientific basis of trivalent actinide-lanthanide separations". United States. doi:.
@article{osti_22264127,
title = {Advancing the scientific basis of trivalent actinide-lanthanide separations},
author = {Nash, K.L.},
abstractNote = {For advanced fuel cycles designed to support transmutation of transplutonium actinides, several options have been demonstrated for process-scale aqueous separations for U, Np, Pu management and for partitioning of trivalent actinides and fission product lanthanides away from other fission products. The more difficult mutual separation of Am/Cm from La-Tb remains the subject of considerable fundamental and applied research. The chemical separations literature teaches that the most productive alternatives to pursue are those based on ligand donor atoms less electronegative than O, specifically N- and S-containing complexants and chloride ion (Cl{sup -}). These 'soft-donor' atoms have exhibited usable selectivity in their bonding interactions with trivalent actinides relative to lanthanides. In this report, selected features of soft donor reagent design, characterization and application development will be discussed. The roles of thiocyanate, aminopoly-carboxylic acids and lactate in separation processes are detailed. (authors)},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2013,
month = 7
}

Conference:
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