File(s) under permanent embargo
Reason: This item is currently closed access.
The solubility of technetium(IV) at high pH
journal contribution
posted on 2008-01-15, 16:55 authored by Peter Warwick, S. Aldridge, Nick Evans, Sarah VinesTechnetium-99 is a β-emitting fission product of 238U. It is important when considering a safety case for nuclear
waste disposal because of its high yield in radioactive waste and long half-life. The aqueous chemistry of Tc in a
cementitious repository is likely to be dominated by Tc(VII), as TcO4
-, in aerobic areas and by Tc(IV), as TcO2 (am),
in anaerobic.
Some previous studies have shown an increase in Tc(IV) solubiltiy with increasing pH above pH 9.5 whilst others
have not observed this increase. This study found that the solubility of Tc(IV) remains independent of pH until
around 13.5, when a small increase can be seen which continues to increase linearly with pH. Modelling suggests
that this increase occurs as the species TcO(OH)3
- is formed. The formation constant was estimated with data from
this study and was found to be log K2 = -21.6 ± 0.3.
History
School
- Science
Department
- Chemistry
Citation
WARWICK, P. ... et al, 2007. The solubility of technetium(IV) at high pH. Radiochimica Acta, 95 (12), pp. 709-716Publisher
© OldenbourgPublication date
2007Notes
This article is Restricted Access. It was published in the journal Radiochimica Acta [© Oldenbourg] and can be found at: http://www.atypon-link.com/OLD/loi/ractISSN
0033-8230Language
- en