Glass matrices: synthesis and long-term behavior

This teaching unit addresses various aspects related to the synthesis, characterization, and long-term behavior of glass matrices. An initial aspect concerning the methodology for studying the long-term behavior of glass matrices under weathering conditions will be developed, specifying in particular the initial characteristics of the materials, the key phenomena governing their behavior, and the appropriate predictive models. Subsequently, the phenomena of leaching and aging under irradiation of glassy materials will be addressed. These different concepts will be supported by a case study on the long-term behavior of nuclear glasses.

Hourly volumes:

            CM: 12 p.m.

            Tutorial: 8 hours

The objective of this teaching unit is to understand the methodology used to predict the behavior of nuclear glasses with a view to long-term high-level and long-period conditioning, and to acquire the knowledge necessary to understand the solid/liquid interface and its evolution under geological formation storage conditions.

Basic elements of radioactivity

Fuel cycle: from mining to waste management

Continuous assessment

Methodology for studying long-term behavior 

• Initial characteristics of materials, characteristics and evolution of geological storage (thermal, hydraulic, mechanical, and chemical)
• Key phenomena governing the behavior of materials
• Predictive modeling and validation
• Leaching of glassy materials:
• Modes of alteration
• Solid-solution interface (double layer and surface charges, adsorption, hydrolysis, condensation, and precipitation phenomena)
• Dissolution kinetics, control by chemical reaction
  • Reaction rate, reaction orders, rate constant and activation energy, solubility product and thermodynamic equilibrium
  • Transition state theory. General law of mineral dissolution
  • Experimental devices for studying dissolution
• Transport at interfaces (diffusion of aqueous species, porous media)
• Nature and role of weathering products (gel, secondary mineral phases)
• Effect of the main storage parameters on kinetics: temperature, solution composition, environmental materials, etc. Mechanisms of catalysis, inhibition, adsorption
• Aging of glassy materials under self-irradiation
• Case studies: long-term behavior of nuclear waste in geological storage conditions:
• Construction of an envelope model
• Application in the case of R7T7 glass stored in clayey soil
• Validation elements: natural and archaeological analogues

Administrative contact(s): Master's in Chemistry Secretariat

Master's degree in Chemistry @ umontpellier.fr