226Ra irradiation to produce 225Ac and 213Bi in an accelerator-driven system reactor

This study aims to produce Th-229 using an innovative nuclear reactor concept, i.e., accelerator-driven system (ADS) reactor. Herein, we investigated the feasibility of producing Th-229 from neutron transmutation of Ra-226 to expand the availability of Ac-225 and Bi-213 in a simple model of ADS reactor. ADS reactor comprises two zones, i.e., an inner zone with a fast neutron spectrum and outer zone with thermal neutron spectrum, which is a subcritical core coupled with an external neutron source. Transmutation behavior, activity, and mass ratio of the obtained isotopes were investigated using the Monte-Carlo tool. In addition with offering the capability, flexibility, and safety of radioactive waste transmutation, the proposed ADS model provides high Th-229 yield and requires less time than a critical reactor with the same neutron flux and irradiated quantity of Ra-226.