Preparation
Milled uranium ore—U3O8 or "yellowcake"—is dissolved in nitric acid, yielding a solution of uranyl nitrate UO2(NO3)2. Pure uranyl nitrate is obtained by solvent extraction, then treated with ammonia to produce ammonium diuranate ("ADU", (NH4)2U2O7). Reduction with hydrogen gives UO2, which is converted with hydrofluoric acid (HF) to uranium tetrafluoride, UF4. Oxidation with fluorine yields UF6.
During nuclear reprocessing, uranium is reacted with chlorine trifluoride to give UF6:
U + 2 ClF3 →UF6 + Cl2
Read more about this topic: Uranium Hexafluoride
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