Methods for separating medical isotopes using ionic liquids

Luo, Huimin; Boll, Rose Ann; Bell, Jason Richard; Dai, Sheng

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DOE OSTI · 1160264

Methods for separating medical isotopes using ionic liquids

Luo, Huimin·Boll, Rose Ann·Bell, Jason Richard·Dai, Sheng

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Abstract

A method for extracting a radioisotope from an aqueous solution, the method comprising: a) intimately mixing a non-chelating ionic liquid with the aqueous solution to transfer at least a portion of said radioisotope to said non-chelating ionic liquid; and b) separating the non-chelating ionic liquid from the aqueous solution. In preferred embodiments, the method achieves an extraction efficiency of at least 80%, or a separation factor of at least 1.times.10.sup.4 when more than one radioisotope is included in the aqueous solution. In particular embodiments, the method is applied to the separation of medical isotopes pairs, such as Th from Ac (Th-229/Ac-225, Ac-227/Th-227), or Ra from Ac (Ac-225 and Ra-225, Ac-227 and Ra-223), or Ra from Th (Th-227 and Ra-223, Th-229 and Ra-225).

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Luo, Huimin, Boll, Rose Ann, Bell, Jason Richard, Dai, Sheng. 2014-10-21. Methods for separating medical isotopes using ionic liquids. https://www.osti.gov/biblio/1160264

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