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DOE OSTI · 1482995

Final Technical Report on Fluoride Salt Study

Hoover, Robert O.·Herrmann, Steven D.·Fredrickson, Guy L.
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Abstract

This report fulfills the Level 3 Milestone No. M3FT-15IN0311022 titled, “Uranium Electrorefining Using Fluoride Salt” within the Department of Energy (DOE) Work Package No. FT-15IN031102 titled, “U/TRU Codeposition and Fluoride Salt Studies – INL”. This work package falls under the Fuel Cycle Research and Development (FCR&D) Materials Recovery and Waste Form Development (MRWFD) Program 1.02.03.11 titled “Domestic Echem”. The electrorefining of uranium in a LiF-NaF-KF, or FLiNaK, salt containing UF 3 has been performed. Several gram-scale electrodeposits of uranium were collected exhibiting a dendritic morphology similar to uranium electrorefining in chloride salts. Additionally, cyclic voltammetry experiments have been performed at 773 K in FLiNaK-UF 4 , FLiNaK-UF 3 , and FLiNaK-UF 3 -LaF 3 salt mixtures to analyze the feasibility of electrorefining uranium in the FLiNaK salt containing lanthanides. Results are promising, showing a 0.48 V potential window between uranium and lanthanum depositions.

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Hoover, Robert O., Herrmann, Steven D., Fredrickson, Guy L.. 2015-09-18. Final Technical Report on Fluoride Salt Study. https://doi.org/10.2172/1482995

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