Reprocessing and direct storage of nuclear fuels

This teaching unit covers the concepts necessary to understand the dissolution or leaching/alteration of ceramic-type materials. In the case of nuclear fuel materials, this involves analyzing degradation phenomena under aggressive conditions representative of a recycling or reprocessing stage, as well as those related to their alteration under more "mild" conditions representative of direct storage in deep geological formations.

Hourly volumes:

            CM: 12 p.m.

            Tutorial: 8 hours

The objective of this teaching unit is to address issues related to the behavior of ceramic materials under chemical stress (dissolution, leaching, alteration). The aim is to establish the drivers of dissolution (conditions representative of a reprocessing operation) or leaching (conditions representative of direct storage) of a ceramic material, considering not only the solid (microstructure, densification, texture, topology, composition) but also the species in solution (acid-base, redox, or complexation drivers).

Fuel cycle: from mining to waste management

Synthesis and remanufacturing of combustible materials

Continuous assessment

• Dissolution/leaching of ceramic materials for the purpose of reprocessing or medium- or long-term storage:
• Description of experimental protocols:
• Analytical strategy related to the evaluation of elementary relaxations
• Tools for characterizing evolving interfaces
• Kinetic approach:
• Effect of structural, microstructural, and textural parameters
• Correlations: synthesis – sintering – dissolution
• Effect of chemical stresses (acid-base, redox, complexation, etc.)
• Thermodynamic approach:
• Description of interface-modifying phenomena
• Identification and control of saturation phenomena (newly formed phases, undissolved dissolution) - Impact on short-, medium-, and long-term behavior
• Irradiation/dissolution or leaching combinations: radiolytic effects.

Lectures and tutorials will be supplemented by bibliographic tutorials and several case studies dealing with the reprocessing of spent nuclear fuel or its long-term behavior with a view to direct storage in deep geological formations.

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

Master's degree in Chemistry @ umontpellier.fr