Investigating material attractiveness of minor actinides fuel for waste
transmutation

Radiotoxicity of nuclear waste is dominated by fission products in the first ~500 years, while for longer times long-lived transuranic elements play a larger role. The main purpose of partitioning and transmutation (P&T) is to transform nuclides that represent a long-term source of heat and radiotoxicity, such as plutonium and minor actinides (MAs) into stable and short-lived nuclides. The use of nitride fuel for fast reactors has gained attention because besides its higher melting point and thermal conductivity compared to oxide fuels. Additionally, actinide mononitride can accommodate a wide range of MA compositions, enabling nitride fuels to be used for transmutation in fast reactors. However, studies of non-proliferation implications of using such fuel are scarce. In this paper we present results related to investigation of material attractiveness plutonium produced during irradiation of americium-neptunium nitride fuel, intended to fuel a lead-cooled reactor. The plutonium content in the spent MA nitride fuel was evaluated in light of material properties known to impact the usability of the material in the manufacture of nuclear explosive devices. The material attractiveness evaluation was done using simulations and material attractiveness figures-of-merit suggested in earlier works.