This report describes the work carried out by the Belgian Nuclear Research Centre in the collaborative research project for IAEA CRP1813 on processing technologies for high level waste, formulation of matrices and characterization of waste forms. Based on the general knowledge about the glass alteration in aqueous conditions at neutral pH, a set of experiments was performed, allowing to determine the glass alteration rate, and to identify the key mechanisms responsible for the glass alteration in Supercontainer conditions. International Simplified Glass (ISG) was altered at 30°C and 70°C in contact with synthetic cement waters at pH ranging from 11.7 to 13.5 or KOH solution at pH 9. A comparison with data from SON68 glass alteration in the same alkaline solutions shows a similar behaviour for both glasses. The difference in the kinetic reactions is very small and the main discrepancy is observed for test conducted at 70°C in YCWCa at pH 13.5. Surface analyses are still necessary to give more information about the alteration layer and the secondary phase formation.
|Number of pages||30|
|State||Published - Sep 2014|
|Publisher||Studiecentrum voor Kernenergie|