Separation of Molybdenum from Uranium(III) and Lanthanide(III) in the Chloride Melt via One-Step Carbidation

High Resolution Image Download MS PowerPoint Slide The separation of Mo from irradiated uranium fuel is an effective way to obtain the radioisotope 99 Mo with crucial roles in clinical nuclear diagnostics. Although the aqueous-based methods have been employed for this purpose, they still suffer from problems such as the generation of large amounts of radioactive liquid waste. Herein, a novel molten salt-based carbidation method is proposed for the efficient separation of Mo from simulated irradiated fuel with uranium and lanthanide ions coexisting in the LiCl-KCl melt. The effects of carbidation temperature and time as well as the amount of the carbidation reagent carbon black were investigated. It is demonstrated that 99.9% Mo is separated in the form of Mo 2 C from the MoCl 3 -UCl 3 -LnCl 3 -LiCl-KCl melt after a reaction with carbon black at a C/Mo ratio of 5:1 at 800°C for 120 min, whereas over 99% of uranium and 98% of lanthanide ions remain in the melt. Neither the separation process nor the separation result is affected by γ and β irradiation. The separated Mo 2 C can be conveniently converted into aqueous Na 2 MoO 4 through calcination followed by dissolution in NaOH solution, achieving a total Mo recovery rate of 97.8%.