Similarities and differences in the behavior of technetium (Tc) and rhenium (Re) in borosilicate waste glasses are described based on results from X-ray absorption and Raman spectroscopies. Hydrothermal glass alteration (vapor hydration tests (VHT) at 200 oC from 23 to 30 days) reveals further behavior differences of these species that may be significant for waste form performance studies. Tc is more sensitive to redox conditions than Re with respect to glass synthesis conditions and VHT alteration processes. Starting glasses with mostly Tc(VII) can have Tc concentrations in the VHT altered layers that are greater than those in the unaltered glass. Starting glasses with significant amounts of Tc(IV) have Tc concentrations in the VHT altered layers that are equal to or less than those in the unaltered glass. Compared to Tc, Re is generally more oxidized and has similar VHT spatial distributions in some samples, with very different distributions in others.

Tc and Re behavior in borosilicate waste glass vapor hydration tests

243rd National Meeting (2012)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.