Feasibility of ¹⁵³Sm production using MNSR research reactor through a multi-stage approach

The main objective of this study was to explore the feasibility of producing ¹⁵³Sm radioisotope in miniature neutron source reactors (MNSRs) in Isfahan-Iran. As the first step of this study, the MNSR's geometry was created by using the MCNP6.2 simulation code and afterwards a validity check was performed by comparing the results with the experimental data. Then, by applying values obtained through simulation, the production process was followed up to 20 irradiation cycles using different irradiation and cooling periods (irradiation setups). The results showed that the proposed simulation technique has an acceptable agreement with the experiments (with a difference of nearly 6%). In spite of limitations, such as irradiation time and flux in such reactors, our results showed that by choosing the correct irradiation setup, it is possible to produces ¹⁵³Sm up to 852.26 mCi g^-1 in 20 successive irradiation cycles. However, after the 10th cycle, the production reached 90% of the maximum point. Nevertheless, the continuance of the irradiation process with a new target (by 10 plus 10 discrete irradiation) can double the total activity in comparison with 20 successive irradiation cycles, without any increase in the fuel consumption of the reactor. These findings increase the prospect of a large-scale production of the life-saving ¹⁵³Sm radioisotope in MNSR reactors.