article posted 29 March 2016
Dr. Olivier Pinet
CEA - French Alternative Energies and Atomic Energy Commission - Waste Conditioning research department - Marcoule (France)
Head Manager of the Research laboratory for the development of conditioning matrices
Role of noble metal on nuclear glass properties
O. Pinet*, M. Neyret, A. Laplace
CEA, DEN, DTCD/SECM/LDMC - Marcoule, F-30207 Bagnols-sur-Cèze, France
Vitrification is one of the recommended immobilization routes for nuclear waste, and is currently implemented on an industrial scale for high-level waste coming from spent fuel reprocessing. High Level Waste glass contains dispersed non dissolved particles of noble metals.
These noble metals can affect significantly some major glass melt properties as rheological behaviour, redox state of multivalent elements, electrical resistivity, vitrification kinetics, crystallization. In order to be able to implement vitrification process with a high waste loading rate a good understanding and measuring of glass containing noble metals properties are necessary.
The presentation is an overview of noble metal impact on nuclear glass properties. Glass melt rheological behaviour is non newtonian contrary to homogeneous glass melt. An electronic conduction signal is detected in addition to usual ionic conduction. The impact range depends mainly on noble metal concentration, morphology and redox.