| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Accelerated Qualification of Nuclear Materials Integrating Experiments, Modeling, and Theories
|
| Presentation Title |
E-1: Characterization of Alkylammonium Functionalized Smectite Organoclays from Molecular Dynamics Simulations |
| Author(s) |
R. Seaton Ullberg, An T. Ta, Emily Maulden, Elizabeth J Gager, Maxime Pouvreau, Juan C. Nino, Nathalie A. Wall, James E. Szecsody, Carolyn Pearce, Simon R. Phillpot |
| On-Site Speaker (Planned) |
R. Seaton Ullberg |
| Abstract Scope |
In recently proposed nuclear waste repositories, functionalized smectite clays are being considered as buffer materials to restrict radionuclide transport into the surrounding biosphere. One promising functionalization strategy is the inclusion of alkylammonium compounds in the clay’s interlayer region. Experimental work has shown this methodology to be effective in sequestering pertechnetate (TcO4-), but the atomistic mechanisms driving this process are poorly understood. In this work, we use molecular dynamics simulations of the functionalized interlayer region to characterize the orientation and diffusivity of multiple alkylammonium compounds ranging from linear to quaternary in structure. Each alkylammonium compound is simulated at a number of different concentrations yielding a rich dataset of molecular dynamics trajectories from which key molecular and bulk properties are assessed for their impact on interlayer structure and sequestration performance. Computational results are coupled with experimental observations to inform a robust understanding of the radionuclide sequestration process in functionalized clay buffer materials. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Nuclear Materials, |