First-principles simulation of corrosion processes relevant to long-term technetium disposition via incorporation in metal alloy waste forms
EMSL Project ID
43690
Abstract
The selection of an appropriate method for the disposition of long-lived radioisotopes resulting from fission processes in nuclear reactors is an exceptionally challenging problem. Particularly challenging is the fact that the long-term stabilities of most materials at the timescales being considered are very hard to determine from an experimental standpoint. In the construction of metallic alloy waste forms designed to hold technetium metal, for example, electrochemical-based models are presently being developed, and it is the intent that such models will be fitted to corrosion data currently being collected from experiments at partner laboratories. However, the fundamental mechanisms of many of the microscopic processes that control these electrochemical corrosion reactions remain unknown, thus obfuscating somewhat the construction of an appropriate model. Furthermore, the models contain many microscopic steps that are difficult to decouple from an experimental investigation. First-principles modeling, on the other hand, has undergone an explosive growth in recent decades exactly due to the capability researchers now have to model such microscopic processes at the quantum mechanical level. We propose to apply the high performance computing resources provided by the Chinook cluster at PNNL to the prediction of the likely thermodynamic stability of these metal alloy waste forms, and their reactivities under various kinds of oxidizing conditions (primarily water and atmospheric oxygen).
Project Details
Project type
Exploratory Research
Start Date
2011-04-01
End Date
2012-04-01
Status
Closed
Released Data Link
Team
Principal Investigator
Related Publications
Kim E, AB Mohrland, PF Weck, T Pang, KR Czerwinski, and D Tomanek. 2014. "Magic Numbers in Small Iron Clusters: A First-Principles Study." Chemical Physics Letters 613:59-63. doi:10.1016/j.cplett.2014.08.056