Conceptual design of direct 99mTc production facility at the high temperature engineering test reactor

Abstract This study proposed a conceptual design of direct 99m Tc production facility from a natural MoO 3 target at the high temperature engineering test reactor (HTTR). 99m Tc is produced by a beta decay of 99 Mo, which is formed via the 98 Mo(n,γ) 99 Mo reaction. 99m Tc is then extracted from the MoO 3 target by sublimation method to take advantage of the high temperature of the HTTR core. The foremost advantage of this concept is that the MoO 3 target is heated up inside the reactor without pulling out for external electric heating, and as a result, 99m Tc could be extracted directly during irradiation. The daily production rate of 99m Tc was estimated to about 9.5 × 10 5  MBq/day with 1 kg MoO 3 target, accounting for 60% daily demand in Japan. With large space available for irradiation purpose, the size of MoO 3 target could be increased, and therefore the HTTR has the capability to supply enough amount of 99m Tc for daily demand in Japan.