Production of 99Mo for Nuclear Medicine by 100Mo(n,2n)99Mo

We have proposed a new route to produce ⁹⁹Mo for nuclear medicine by the ¹⁰⁰Mo(n,2n)⁹⁹Mo reaction. The reaction cross section is known to be ∼1.5 b in the neutron energy, E_n, range from 12 to 17 MeV: 10-times larger than the thermal-neutron capture cross section of ⁹⁸Mo. By irradiating an enriched ¹⁰⁰Mo target for 198 h with neutrons of ∼10¹³ n/(cm² s) at E_n∼ 14 MeV, one can produce 79 GBq/g specific activity of ⁹⁹Mo. Since the cross sections for ¹⁰⁰Mo(n, p)¹⁰⁰Nb, ¹⁰⁰Mo(n,n p)⁹⁹Nb and ¹⁰⁰Mo(n,α)⁹⁷Zr at 12≤ E_n≤ 17 MeV are small, less than a few mb, radioactive waste during and/or after chemical processing of ⁹⁹Mo would not be a serious problem. The proposed route could bring a major breakthrough in the solution of ensuring a constant and reliable supply of ⁹⁹Mo without using highly enriched ²³⁵U.