Thermodynamic Modelling of the Pd-Ru-Te-O for Nuclear High-Level Waste Immobilization - CEA - Commissariat à l’énergie atomique et aux énergies alternatives Accéder directement au contenu
Communication Dans Un Congrès Année : 2020

Thermodynamic Modelling of the Pd-Ru-Te-O for Nuclear High-Level Waste Immobilization

Résumé

Pd and Ru are the main platinoid fission products formed during burnup of nuclear fuels. During fuel reprocessing, these element partly dissolve in nitric acid and they exhibit very low solubility into borosilicate glasses during the vitrification process. Due to their affinity towards tellurium from the fission product solution, palladium mainly precipitates under (Pd-Te) intermetallics [1] and ruthenium is likely to form hcp solid solutions [2]. The composition and microstructures of these phases are also sensitive to oxygen potential [3]; oxydation of ruthenium can lead to needle-shaped or polyhedral (Rh,Ru)O2 oxide phases [4]. These precipitates can affect significantly the physico-chemical properties of the glass melt during melting in hot or cold crucible. For decades, many studies were undertaken at CEA [5] to point out the high temperature interactions of the platinum group metals (PGM) issuing from the calcinated waste. In parallel to these studies, a Calphad database is being developed to address the thermodynamics of such systems to provide an assessment of the PGMs in nuclear waste. This study presents the assessed binary systems. Some calculations are also performed to highlight how this flexible tool makes is used to predict the stability between metallic and oxide phases as a function of temperature and oxygen potential mainly driven by the glass. [1] S. Gossé, C. Guéneau, Intermetallics 19 (2011) 621-629 [2] S. Gossé, N. Dupin, C. Guéneau, J.-C. Crivello, J.-M. Joubert, J. Nuclear Mater 474 (2016) 163-173 [3] S. Gossé, S. Bordier, C. Guéneau, E. Brackx, R. Domenger, J. Rogez, J. Nuclear Mater 500 (2018) 252-264 [4] R. Pflieger, L. Lefebvre, M. Malki, M. Allix, A. Grandjean, J. Nuclear Mater 389 (2009) J. Nuclear Mater, Vol. 389, N°3 [5] O. Pinet, S. Mure, Journal of Non-Crystalline Solids, 355 (2009) 221-227
Fichier non déposé

Dates et versions

cea-04358299 , version 1 (21-12-2023)

Identifiants

  • HAL Id : cea-04358299 , version 1

Citer

Stéphane Gosse, Cloé Laurin, Elise Regnier, Annabelle Laplace-Ploquin, Sophie Schuller. Thermodynamic Modelling of the Pd-Ru-Te-O for Nuclear High-Level Waste Immobilization. MRS 2020 virtual Spring/Fall Meeting, Nov 2020, Boston, United States. ⟨cea-04358299⟩
6 Consultations
0 Téléchargements

Partager

Gmail Facebook X LinkedIn More