Separations of U/Pu and Np/Pu using fluoride volatility

McNamara, Bruce K.; O'Hara, Matthew J.; Morrison, Samuel S.; Soderquist, Chuck Z.; Casella, Andrew M.; Clark, Richard A.; Carter, Rebecca

doi:10.1016/j.jfluchem.2022.109952

DOE OSTI · 1860312

Separations of U/Pu and Np/Pu using fluoride volatility

McNamara, Bruce K.·O'Hara, Matthew J.·Morrison, Samuel S.·Soderquist, Chuck Z.·Casella, Andrew M.·Clark, Richard A.·Carter, Rebecca

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Abstract

Here the importance of uranium/plutonium and neptunium/plutonium separations at large scale or at environmental levels is such that the reactivity of nitrogen trifluoride (NF 3 ) with respect to other fluorinating reagents warranted investigation. We show that NF 3 does not convert PuO 2 or PuF 4 to PuF 6 , during separations of U/Pu and Np/Pu, even under forcing conditions. Herein, this is analytically demonstrated to trace level. This rather exclusive behavior has been reported for only one other reagent: BrF 3 . Confidence in this result now allows for rapid and selective separations of volatile UF 6 and NpF 6 from plutonium. Preliminary data concerning the separation of 233 Pa from 237 Np is also described.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY actinide separations fluoride volatility nitrogen trifluoride

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McNamara, Bruce K., O'Hara, Matthew J., Morrison, Samuel S., Soderquist, Chuck Z., Casella, Andrew M., Clark, Richard A., Carter, Rebecca. 2022-02-12. Separations of U/Pu and Np/Pu using fluoride volatility. https://doi.org/10.1016/j.jfluchem.2022.109952

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