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DOE OSTI · 3016917

Examination of Molten Salt Reactor Relevant Elements Using Hydrothermal Synthesis

Windorff, Cory J.·Chemey, Alexander T.·Sperling, Joseph M.·Klamm, Bonnie E.·Albrecht-Schmitt, Thomas E.
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Abstract

The structural chemistry of elements relevant to the FLiBe molten salt reactor, Th, U, Np, and Zr, including Ce andNd (as analogues for Pu and Am, respectively), have been examined using hydrothermal synthesis at 200 °C. These reactions serve to model the reaction of molten salts under hydrolysis conditions. The results show that U and Np formed LiAnF 5 , while Ce formed Li 4 CeF 8 . The source of U also controlled the crystal quality, where UO 2 gave small crystals, while UO 3 ·2H 2 O gave very large crystals. It is likely that Be incorporation was not observed because of the high solubility of [BeF 4 ] 2– in water. Zr formed a third product, Li 6 BeF 4 ZrF 8 , which features isolated [BeF 4 ] 2– and [ZrF 8 ] 4– units bridged by Li + . Additionally, Li 2 BeF 4 was regularly isolated. As a result, when little to no alkali metal was included in the reaction, M 3 F 12 (H 2 O) was isolated for Np, U, and Ce.

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Windorff, Cory J., Chemey, Alexander T., Sperling, Joseph M., Klamm, Bonnie E., Albrecht-Schmitt, Thomas E.. 2020-03-26. Examination of Molten Salt Reactor Relevant Elements Using Hydrothermal Synthesis. https://doi.org/10.1021/acs.inorgchem.0c00360

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