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DOE OSTI · 1599144

Gas-phase molybdenum-99 separation from uranium dioxide by fluoride volatility using nitrogen trifluoride

McNamara, Bruce K.·O'Hara, Matthew J.·Clark, Richard A.·Morrison, Samuel S.·Soderquist, Chuck Z.·Scheele, Randall D.
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Abstract

Production of the important 99m Tc medical isotope parent, molybdenum-99 ( 99 Mo), via the fissioning of high- and low-enriched uranium (HEU/LEU) targets followed by target dissolution in acid and solution-phase purification of 99 Mo is time-consuming, generates quantities of corrosive radioactive waste, and can result in the release of an array of radionuclides to the atmosphere. An alternative 99 Mo purification method has been devised that has the potential to alleviate many of these issues. Herein, we demonstrate the feasibility of a rapid Mo/Tc gas-phase separation from UO 2 . The results indicate that volatile [ 99 Mo]Mo can be captured downstream of the reacted solid mixture on a column bed (trap) of alumina; the majority of the captured [ 99 Mo]Mo can be subsequently eluted from the alumina trap with a few milliliters of water. >1.0 × 10 5 single pass decontamination of U and the collected [ 99 Mo]Mo product is demonstrated. This simple thermo-fluorination technique has the potential to provide a rapid methodology for routine 99 Mo production.

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McNamara, Bruce K., O'Hara, Matthew J., Clark, Richard A., Morrison, Samuel S., Soderquist, Chuck Z., Scheele, Randall D.. 2020-01-21. Gas-phase molybdenum-99 separation from uranium dioxide by fluoride volatility using nitrogen trifluoride. https://doi.org/10.1039/c9ra10270a

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