Non-linearity in glass composition dependence of dissolution rates: Effect of solution pH
Conference
·
OSTI ID:47898
- Catholic Univ. of America, Washington, DC (United States)
In our previous studies on the optimization of glass compositions for high-level nuclear waste vitrification it was found that, over certain composition ranges, PCT leachate concentrations increased dramatically with very small changes in glass composition. The large differences that are observed between the leachate pH values for the {open_quotes}durable{close_quotes} and the {open_quotes}less-durable{close_quotes} glasses is one possible cause for this strongly non-linear glass composition effect; conversely, the pH difference may be merely another symptom. In this study, four simulated nuclear waste glasses (two of the less-durable and two of the durable types), were leached in both zwitterionic and inorganic buffer solutions, at fixed pH-values in the ranges of 7 to 12. The very different leaching behaviors of the two types of glasses persisted and, furthermore, different pH-dependence was found despite their very similar glass composition. This study suggests that the leachate pH difference observed between the less-durable and the durable glasses under uncontrolled pH conditions is not the major cause of the large difference of leaching behavior between those glasses. The normalized release ratios of soluble components (B, Li, Na) to Si show significant differences for the two types of glasses.
- OSTI ID:
- 47898
- Report Number(s):
- CONF-931108--Vol.333
- Country of Publication:
- United States
- Language:
- English
Similar Records
Durability of a fluoride-containing low-level mixed waste glass: Effect of pH
Long-term comparison of dissolution behavior between fully radioactive and simulated nuclear waste glasses
Canonical correlation of waste glass compositions and durability, including pH
Conference
·
Fri Dec 30 23:00:00 EST 1994
·
OSTI ID:39182
Long-term comparison of dissolution behavior between fully radioactive and simulated nuclear waste glasses
Journal Article
·
Sun Oct 31 23:00:00 EST 1993
· Nuclear Technology; (United States)
·
OSTI ID:5894307
Canonical correlation of waste glass compositions and durability, including pH
Conference
·
Sat May 01 00:00:00 EDT 1993
·
OSTI ID:10161593