Conceptual design of direct ~(99m)Tc production facility at the high temperature engineering test reactor

摘要

This study proposed a conceptual design of direct Tc-99m production facility from a natural MoO3 target at the high temperature engineering test reactor (HTTR). Tc-99m is produced by a beta decay of Mo-99, which is formed via the Mo-98(n,gamma) Mo-99 reaction. Tc-99m is then extracted from the MoO3 target by sublimation method to take advantage of the high temperature of the HTTR core. The foremost advantage of this concept is that the MoO3 target is heated up inside the reactor without pulling out for external electric heating, and as a result, Tc-99m could be extracted directly during irradiation. The daily production rate of Tc-99m was estimated to about 9.5 x 10(5) MBq/day with 1 kg MoO3 target, accounting for 60% daily demand in Japan. With large space available for irradiation purpose, the size of MoO3 target could be increased, and therefore the HTTR has the capability to supply enough amount of Tc-99m for daily demand in Japan.