Research on nitride fuel for transmutation of minor actinides

Minato, Kazuo ; Arai, Yasuo; Akabori, Mitsuo; Nakajima, Kunihisa  

In the Japan Atomic Energy Research Institute (JAERI), the concept of the transmutation of minor actinides (MA: Np, Am and Cm) with accelerator-driven systems (ADS) is being studied, where MA nitride is adopted as a fuel material of sub-critical core. The nitride fuel has been chosen as a candidate because of the possible mutual solubility among the actinide mononitrides and excellent thermal properties besides supporting hard neutron spectrum. Highly enriched N-15 would have to be used for the nitride fuel in order to prevent the formation of hazardous C-14. By applying pyrochemical process in the treatment of spent fuel, N-15 could be readily recovered and recycled. The present paper describes an overview of the research on the nitride fuel performed in JAERI. Fabrication experiments of actinide nitrides, measurements of vaporization behavior and thermal properties, and irradiation tests of actinide nitrides are summarized.