Evaluation of Mo/Tc production with irradiated MoO pellets

Ishida, Takuya; Shiina, Takayuki*; Ota, Akio*; Suzuki, Yoshitaka   ; Shibata, Akira ; Nishikata, Kaori ; Kimura, Akihiro ; Tanase, Masakazu*; Kobayashi, Masaaki*; Sano, Tadafumi*; Fujihara, Yasuyuki*; Tsuchiya, Kunihiko 

Technetium-99m (Tc) is one of the radioisotopes which are used most as radiopharmaceuticals, and it is obtained from the parent nuclide of Molybdenum-99 (Mo). However, the specific radioactivity of Mo by (n, ) method is extremely low compared with that by fission method ((n,f) method), and as a result, the radioactive concentration of the extracted Tc solution is also low. Thus, it is necessary for the high radioactive concentration of the Tc solution to develop the Mo/Tc separation/extraction/concentration method. In this study, the experiments of Mo/Tc production were performed to enhance recovery yields of Tc and to get a high quality of Tc product. The procedures are described as follows. (1) High-density MoO pellets were irradiated in the Kyoto University Research Reactor (KUR). (2) Tc was extracted with MEK. (3) Tc extracted in MEK was purified and concentrated with acidic alumina column. (4) Product of Tc solution was checked in several factors such as radionuclidic and radiochemical purities. The irradiated MoO pellets were dissolved in 6M-NaOH and the Mo/Tc solution was treated with the devices. From the results, the Tc recovery yields achieved 805% of our goal. Finally, the extracted Tc solution passed the quality inspection of six items.