Effect of Al(NO₃)₃ on Extraction of Am, Cm, Eu, and Ce(III) by 18-Crown-6 and Mixtures of 18-Crown-6 and Chlorinated Cobalt Dicarbolliede in Nitrobeneze

Abstract

The extraction of Am, Cm, Eu, and Ce(III) tracers from nitric acid in the presence of Al(NO₃)₃ 18-crown-6 (18C6) or mixtures of 18C6 and chlorinated cobalt dicarbollide (ChCoD) in nitrobenzene solutions was investigated. The partitioning of 18C6 between nitrobenzene and the aqueous phase was also investigated. In the presence of Al(NO₃)₃, 18C6 is selective for Ce over Am, Cm, and Eu. The extraction of these same metals by ChCoD is suppressed by Al(NO₃)₃. The extraction of these metals is a complicated function of the 18C6-ChCoD concentration ratio. The probable formation of a 1:1 18C6:ChCoD complex and the effects of ionic strength and pH on the extraction are discussed.

ACKNOWLEDGMENTS

We are grateful to the US Department of Commerce and the Efficient Separations and Processing Integrated Program of the US Department of Energy for jointly supporting the Special American Business Internship Training program at Pacific Northwest Laboratory, through which V.V.R. obtained an internship, and to the Khlopin Radium Institute for suggesting and supporting the work. Pacific Northwest Laboratory is operated by Battelle Memorial Institute for the US Department of Energy under Contract DE-AC06-76RLO-1830.