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Title: Selective electrochemical capture and release of uranyl from aqueous alkali, lanthanide, and actinide mixtures using redox-switchable carboranes
We report the selective electrochemical biphasic capture of the uranyl cation (UO 2 2+ ) from mixed-metal alkali (Cs + ), lanthanide (Nd 3+ , Sm 3+ ), and actinide (Th 4+ , UO 2 2+ ) aqueous solutions to an organic, 1,2-dichloroethane (DCE), phase using the ortho -substituted nido -carborane anion, [1,2-(Ph 2 PO) 2 -1,2-C 2 B 10 H 10 ] 2− (POCb2−). The reduced POCb2− is generated by electrochemical reduction of the closo -carborane, POCb, prior to mixing with the aqueous mixed-metal solution. Subsequent UO 2 2+ release from the captured product, [UO2(POCb)2]2−, was performed by galvanostatic bulk electrolysis of the DCE phase and back-extraction of UO 2 2+ to a fresh aqueous phase. The selective capture and release of UO 2 2+ was confirmed by combined ICP-OES and NMR spectral analyses of the aqueous and organic phases, respectively, against the newly synthesized nido -carborane complexes, [[CoCp*2][Cs(POCb)]]2, [CoCp*2]3[Nd(POCb)3], [CoCp*2]3[Sm(POCb)3], and [CoCp*2]2[Th(POCb)3].  more » « less
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Journal Name:
Chemical Science
Page Range / eLocation ID:
3369 to 3374
Medium: X
Sponsoring Org:
National Science Foundation
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