Synthesis of Yttria-Stabilised Zirconia Matrices for Immobilisation of Actinides by Internal Gelation Method

In the scope of the co-conversion of actinides solutions obtained from partitioning spent nuclear fuel, the internal gelation of ceria-doped yttria-stabilized zirconia was investigated. This dust-free method to fabricate kernels, which can be used as fuel or pressed into pellets, is technically easy to implement and compatible with remote handling. The effects of the quantity of reactants used on the properties of the material were studied. Gels, kernels and pellets were analyzed by thermal analysis, electron microscopy and X-ray diffraction. It was found that the initial broth composition played an important role in the structure of kernels and the formation of cracks during thermal treatment. Pellets obtained with a repressing method were found to present densities up to 86% TD.