Development of High Density MoO3 Pellets for Production of 99Mo Medical Isotope

99mTc is the most widely used radioisotope in diagnostic radiopharmanceuticals. However, the supply of 99Mo, the parent nuclide of 99mTc, in Japan depends entirely on the import from foreign countries. Thus, it is necessary to supply 99Mo stably by the domestic production, because of the unplanned shutdown and aged state of the foreign countries' reactors for 99Mo production. Japan Atomic Energy Agency (JAEA) has a plan to produce 99Mo. It is necessary that increasing of target volume for supplying 99Mo stably. Pellets as irradiation target was studied. It is difficult to produce the pellets with high density, because MoO3 sublimes at low temperature. In this study, MoO3 pellets were produced by two kinds of production methods and characterization of these pellets were carried out. MoO3 pellets were produced by the cold pressing sintering (CIP) method at first. Next, MoO3 pellets were produced by the Spark Plasma Sintering (SPS) method. As a result, high density MoO3 pellets were produced by the SPS method and the characteristics of the MoO3 pellets were confirmed.