The Commissariat à l’Énergie Atomique Spin Program: Minor Actinide Fuel and Target Aspects

The strategy and main results of fuel and target transmutation studies are reviewed with emphasis on out-of-pile and in-pile behavior issues. All this work is coordinated in the unique French project Sèparation-Incineration (SPIN) by the Commissariat à̅ l̅’Énergie A̅t̅omique with the support of its industrial partners Electricité de France, Framatome, and Cogema and with some work performed in the frame of international collaborations. This work is a contribution to the French SPIN program, which in part is studying the feasibility of separation and transmutation of minor actinides, to reduce the long-term risk of geological disposal. Specifically; this research pertains to fuel and targets containing neptunium and americium for irradiation in both fast reactors and pressurized water reactors. Primary interest is shown in the heterogeneous mode in which AmO2 and NpO2 are contained in an inert matrix such as an oxide or nitride ceramic or a refractory metal. The required characteristics of these matrices are outlined, the suitability of several candidate materials is discussed, and experimental results are presented.