Investigation of Ion Exchange and Its Impact on Radionuclide Release and Surface Reactivity in Glass Waste Forms
EMSL Project ID
50133
Abstract
Due to the long lifetimes of radionuclide species found in nuclear waste, the vitrified waste forms need to retain all hazardous species for thousands of years. With the current inability to replicate these long times in a laboratory setting, calculations and models are enlisted to estimate radionuclide release rates. Understanding the mechanisms behind glass dissolution allows for the development and refinement of the elemental release rates which helps to accurately determine how much hazardous material can be expected to release into the environment over time. One mechanism of particular interest is ion exchange which is typically characterized by measuring elemental profiles in the bulk material and/or measuring elemental concentrations in solution. Characterization of corroded glasses will be achieved by leveraging the unique analytical tools in EMSL (SEM, APT, ToF-SIMS, NMR) to obtain a better understanding of the movement of mobile ions from the unaltered glass network, through the alteration layer, and into solution. The main objective of the proposed work is the development of an improved glass corrosion model that calculates ion exchange rates of low-activity waste glasses in an accurate and predictive manner using EMSL’s unique analytical capabilities.
Project Details
Start Date
2018-02-16
End Date
2018-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members