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Title: Accomplishing simple, solubility-based separations of rare earth elements with complexes bearing size-sensitive molecular apertures

Journal Article · · Proceedings of the National Academy of Sciences of the United States of America
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  1. P. Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104
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Rare earth (RE) metals are critical components of electronic materials and permanent magnets. Recycling of consumer materials is a promising new source of rare REs. To incentivize recycling, there is a clear need for the development of simple methods for targeted separations of mixtures of RE metal salts. Metal complexes of a tripodal hydroxylaminato ligand, TriNOx3–, featured a size-sensitive aperture formed of its three η2-(N,O) ligand arms. Exposure of cations in the aperture induced a self-associative equilibrium comprising RE(TriNOx)THF and [RE(TriNOx)]2 species. Differences in the equilibrium constants Kdimer for early and late metals enabled simple separations through leaching. Separations were performed on RE1/RE2 mixtures, where RE1 = La–Sm and RE2 = Gd–Lu, with emphasis on Eu/Y separations for potential applications in the recycling of phosphor waste from compact fluorescent light bulbs. Using the leaching method, separations factors approaching 2,000 were obtained for early–late RE combinations. Finally, following solvent optimization, >95% pure samples of Eu were obtained with a 67% recovery for the technologically relevant Eu/Y separation.

Research Organization:
Univ. of Pennsylvania, Philadelphia, PA (United States)
Sponsoring Organization:
USDOE Office of Science (SC)
Grant/Contract Number:
SC0006518
OSTI ID:
1335528
Alternate ID(s):
OSTI ID: 1465110
Journal Information:
Proceedings of the National Academy of Sciences of the United States of America, Journal Name: Proceedings of the National Academy of Sciences of the United States of America Vol. 113 Journal Issue: 52; ISSN 0027-8424
Publisher:
Proceedings of the National Academy of SciencesCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 42 works
Citation information provided by
Web of Science

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Figures / Tables (10)

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