Skip to Main content Skip to Navigation
Journal articles

The fate of Si and Fe while nuclear glass alters with steel and clay

Abstract : The French concept developed to dispose high-level radioactive waste in geological repository relies on glassy waste forms, isolated from the claystone host rock by steel containers. Understanding interactions between glass and surrounding materials is key for assessing the performance of a such system. Here, isotopically tagged SON68 glass, steel and claystone were studied through an integrated mockup conducted at 50°C for 2.5 years. Post-mortem analyses were performed from nanometric to millimetric scales using TEM, STXM, ToF-SIMS and SEM techniques. The glass alteration layer consisted of a crystallized Fe-rich smectite mineral, close to nontronite, supporting a dissolution/reprecipitation controlling mechanism for glass alteration. The mean glass dissolution rate ranged between 1.6 × 10$_{−2}$ g m$_{−2}$ d$_{−1}$ to 3.0 × 10$_{−2}$ g m$_{−2}$ d$_{−1}$ , a value only 3-5 times lower than the initial dissolution rate. Thermodynamic calculations highlighted a competition between nontronite and protective gel, explaining why in the present conditions the formation of a protective layer is prevented.
Document type :
Journal articles
Complete list of metadata

https://hal-cea.archives-ouvertes.fr/cea-03193704
Contributor : Serge Palacin Connect in order to contact the contributor
Submitted on : Friday, April 9, 2021 - 8:34:48 AM
Last modification on : Tuesday, September 28, 2021 - 5:13:37 PM
Long-term archiving on: : Monday, July 12, 2021 - 9:20:18 AM

File

NPJMaterialsDegrad2021_5_16.pd...
Publisher files allowed on an open archive

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Citation

C. Carriere, P. Dillmann, S. Gin, Delphine Neff, L. Gentaz, et al.. The fate of Si and Fe while nuclear glass alters with steel and clay. npj Materials Degradation, Nature Research 2021, 5 (1), pp.16. ⟨10.1038/s41529-021-00160-x⟩. ⟨cea-03193704⟩

Share

Metrics

Record views

150

Files downloads

141