Temperature Impact on the Sorption of Selenate onto Anatase

The radioactive isotope Selenium-79 is a long-lived fission product found in nuclear waste. Due to its long half live of 3.27 ∙ 105 years [1] it is expected to be one of the most contributing isotopes concerning safety assessments of nuclear waste underground repositories. The control of the mobility and bioavailability of selenium is therefore of great importance for a safe disposal of radioactive waste.
One major process controlling selenium mobility and bioavailability is the adsorption onto mineral surfaces of both the geological and engineered barrier.
The present study focuses on the impact of temperature on the sorption of selenate (SeO42-) onto anatase (TiO2). The sorption of selenate onto anatase at different temperatures (25°C – 60°C) was investigated both with batch experiments and ATR-FT-IR spectroscopy. In order to explain possible differences in sorption at higher temperatures, the surface of the anatase was investigated.