Waste form corrosion modeling: comparison with experimental results

Results of leaching experiments using active and inactively simulated HLW g lass in concentrated NaCl solution are described. Measured solution concent rations of glass components, fission products and actinides are compared wi th computed data. The computed pH value corresponds with the findings from experiments with inactively simulated glass samples. Moreover, the concentr ations of silica and strontium can be described adequately by reaction path modelling. The computed U concentration is explained by the precipitation of schoepite or Na2U2O7. The computed Am concentration significantly exceed s the measured data. This may be attributed to sorption processes on corros ion products of the glass, which are relevant also for lanthanide elements under the conditions of the experiments. This hypothesis is tested by solid solution approaches and by computing sorption of Am onto SiO2 precipitates . (C) 2001 Elsevier Science Ltd. All rights reserved.