Preparation and characterization of multiphase ceramic designer waste forms
Braeden M Clark1, Priyatham Tumurugoti1, Shanmugavelayutham K Sundaram2
1Multifunctional Materials Laboratory (M&M) Lab, Inamori School of Engineering, The New York State College of Ceramics, Alfred University, Alfred, NY, 14802, USA.
Scientific Reports
|February 26, 2021
Summary
This study introduces a designer nuclear waste form for improved long-term performance. These novel ceramic waste forms demonstrate reduced cesium release, aiding in accurate durability assessments.
Area of Science:
- Materials Science
- Nuclear Engineering
- Geochemistry
Background:
- Assessing the long-term performance of multiphase ceramic nuclear waste forms is challenging due to complex microstructures and fabrication variability.
- Correlating laboratory durability tests with real-world environmental performance requires standardized reference materials.
Purpose of the Study:
- To develop a "designer waste form" using spark plasma sintering for controlled microstructure and enhanced durability.
- To create a reference material for comparing the chemical durability of various multiphase ceramic waste forms.
- To investigate the influence of hollandite content on elemental release in designer waste forms.
Main Methods:
- Spark plasma sintering was employed to fabricate dense, monolithic designer waste forms with controlled phase interactions.
- Designer waste forms containing varying hollandite, zirconolite, and pyrochlore ratios were synthesized.
- Product Consistency Test (PCT) and Vapor Hydration Test (VHT) were conducted to evaluate leaching behavior and chemical durability.
Main Results:
- The fabricated designer waste forms exhibited excellent durability, remaining unaffected by the Vapor Hydration Test for 1500 hours.
- Product Consistency Test results showed a decrease in fractional cesium release with increasing hollandite content.
- Elemental release from zirconolite and pyrochlore phases had minimal impact on the overall release from the hollandite phase.
Conclusions:
- Designer waste forms produced via spark plasma sintering offer a promising approach for creating standardized reference materials for nuclear waste form durability testing.
- The increased hollandite content effectively reduces cesium leaching, enhancing the long-term performance of the waste form.
- This approach simplifies the assessment of multiphase ceramic waste forms by isolating the contribution of specific phases to elemental release.
