An investigation of the long-term aqueous corrosion behaviour of glass, crystalline ceramics, and glass-ceramic composite materials
| dc.contributor.advisor | Grosvenor, Andrew Paul | |
| dc.contributor.committeeMember | Ansdell, Kevin Michael | |
| dc.contributor.committeeMember | Scott , Rob William James | |
| dc.contributor.committeeMember | Phenix, Christopher P | |
| dc.contributor.committeeMember | Biesinger, Mark C. | |
| dc.contributor.committeeMember | Kelly, Timothy L | |
| dc.creator | Mikhchian, Mehrnaz | |
| dc.date.accessioned | 2025-02-03T17:33:19Z | |
| dc.date.available | 2025-02-03T17:33:19Z | |
| dc.date.copyright | 2024 | |
| dc.date.created | 2025-01 | |
| dc.date.issued | 2025-02-03 | |
| dc.date.submitted | January 2025 | |
| dc.date.updated | 2025-02-03T17:33:19Z | |
| dc.description.abstract | Nuclear power is considered a clean alternative source of electricity compared to fossil fuels due to low CO2 emissions. The long-term and safe sequestration of high-level radioactive waste (long half-life minor actinides and fission products) remains a key problem for the sustainable development of the nuclear industry. Deep geological repositories are being considered internationally as a future plan for the permanent disposal of high-level radioactive waste (i.e., long half-life minor actinides (Cm, Am, Np, Th), and fission products). A common challenge associated with geological disposal is ground water corrosion and leaching of the radionuclides incorporated in a wasteform into the environment. Glass-ceramic composite materials are being considered as potential nuclear wasteform candidates due to having high waste loading and expected enhanced chemical durability compared to borosilicate glass on its own. However, the long-term aqueous corrosion resistance (i.e., over years) of these glass-ceramic composite materials and how the structure of these materials changes after being exposed to an aqueous environment are not fully understood. This thesis aims to investigate how the long-term aqueous corrosion behaviour of glass, ceramic, and glass-ceramic composite materials change depending on their structure and composition. The aqueous corrosion experiments were performed in triplicate on each glass, ceramic, and glass-ceramic composite material to understand the similarities and differences in the leaching mechanism of these materials over one year of exposure to deionized water. It was found that the structure and composition of wasteform materials (i.e., single phase material vs. multiphase composite material) affect the dissolution mechanisms of glass, ceramic, and glass-ceramic composite materials upon exposure to deionized water. A combination of surface and bulk techniques has been used in this work to provide detailed information on the corrosion that occurs at the surface or bulk regions of these materials after being exposed to deionized water. The results have demonstrated that the corrosion process only occurs at the surface of these materials, and that the long-range structure of these materials was unaffected. The comprehensive surface analyses of the glass and glass-ceramic composite materials have shown that the aqueous corrosion of these materials led to the formation of an amorphous surface layer during the early stages of exposure to deionized water, which could restrict the further release of ions into the deionized water. The aqueous durability of glass-ceramic composite materials was found to be comparable to that of borosilicate glass, indicating that these materials can be considered as potential alternative wasteforms vs. borosilicate glass for the safe and effective sequestration of nuclear waste. | |
| dc.format.mimetype | application/pdf | |
| dc.identifier.uri | https://hdl.handle.net/10388/16536 | |
| dc.language.iso | en | |
| dc.subject | Nuclear wasteform | |
| dc.subject | Aqueous corrosion | |
| dc.subject | Surface chemistry | |
| dc.subject | Leaching rate | |
| dc.title | An investigation of the long-term aqueous corrosion behaviour of glass, crystalline ceramics, and glass-ceramic composite materials | |
| dc.type | Thesis | |
| dc.type.material | text | |
| thesis.degree.department | Chemistry | |
| thesis.degree.discipline | Chemistry | |
| thesis.degree.grantor | University of Saskatchewan | |
| thesis.degree.level | Doctoral | |
| thesis.degree.name | Doctor of Philosophy (Ph.D.) |