Synthesis of the Nuclear Glass Ceramics

The impregnation of these peculiar aerogels is proposed to trap the nuclear wastes in a silica matrix. After a soaking treatment, the host matrix is dried, then sintered. The expected material is a nanocomposite constituted by nuclear wastes crystals embedded into a silica matrix. For safety reasons the lanthanides, Ce and Nd, are used to simulate the III and IV valent actinides [26-28] [for example, Am(III), Cm(III), Np(IV), Pu(IV)]. Nd and Ce as actinides surrogates have been also chosen because of their dissimilar affinity to silica. Hence, Nd and Ce will lead to different kinds of glass-ceramics, simulating the possible behaviors of the actinides in the presence of silica depending on their silica affinity. 

Cerium and neodymium nitrates are dissolved in water and after soaking, the samples are dried and heat treated in such a way to complete the drying and to decompose the nitrates. Further heating at --1,100°C fully sinters the silica network by viscous flow [14,29]. 

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