Dielectric Properties of Uranium and Plutonium Nitrate Solution and the Oxide Compounds Formed in the De-nitratiin Process by the Microwave Heating Method

Kato, Yoshiyuki ; Kurita, Tsutomu ; Abe, Tomoyuki

The application of the fluoride volatility process in the reprocessing of fuel from the fast breeder reactor is regarded as one of the economical methods. Plutonium hexafluoride (PuF), however, reacting with fluorine (F2) and plutonium dioxide (PuO) as the raw material, is in an unstable condition and tends to remain as a solid compound in the process after decomposing into plutonium tetrafluoride (PuF). Suitable conditions should be established for the practical use of this process. One of them is to enhance the stability of PuF. The behaviour of plutonium fluorination and relevant chemical reactions were investigated by referring to sundry literature and by thermodynamic calculation. It was then compared with recent data from laboratory scale experiments for this paper. Results from the theoretical analysis agreed with experimental observation that PuF could be formed stably under a high temperature condition (approx.1000 K) with over supply of figher concentration of F2.