About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Materials and Chemistry for Molten Salt Systems
|
| Presentation Title |
Comparative Study of Oxygen Gas and Oxide Ion Impurities in Chloride Based Molten Salt via Neural Network-Based Atomistic Simulations |
| Author(s) |
Hyeonwoo Kim, Sangtae Kim |
| On-Site Speaker (Planned) |
Hyeonwoo Kim |
| Abstract Scope |
Understanding molten salt behavior under contamination is critical for ensuring pyrochemical safety. This study investigates the density variations and structural evolution of UCl3-based molten salts under O2 gas ingress and O2- ion accumulation using machine learning potential molecular dynamics. We observe opposing density trends: a non-linear decrease for O2 gas versus a linear increase for O2- ions. Atomistic analysis reveals that while O2 gas ingress initially causes local contraction, a topological transition to rigid, corner-sharing uranyl chains dominates at higher concentrations. This network sterically displaces bridging chlorides into voluminous terminal positions, effectively accelerating the macroscopic volume expansion. Conversely, O2- accumulation drives densification through the formation of compact, edge-sharing U-O clusters, inducing a structural contraction that overrides the mass reduction from chloride removal. These distinct density fingerprints offer a robust, mechanism-based diagnostic tool for identifying and managing specific contamination types in nuclear fuel processing. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Nuclear Materials, Modeling and Simulation |