Abstract
In-diffusion experiments for Cs+ and I- in sandstone were performed as a function of ionic strength ([NaCl]=0.01, 0.51M) and tracer concentration ([CsI]=7.5E-5, 1.5E-2M) together with the measurements of the physical and chemical properties of sandstone, and apparent diffusivities (Da) for Cs were obtained. The obtained Da-values for Cs+ scarcely depended on [NaCl], but increased with increasing [Cs+]. This trend is consistent with that of rock capacity factors (α), indicating that distribution coefficient (Kd) onto sandstone and effective diffusivity scarcely depend on [NaCl]. The concentration profiles of I- were all in already breakthrough. Although this indicates that I- diffusion is faster than that of Cs+, the concentration profiles of I may have been lower than those for blank samples, judging synthetically from the correlations between α-values and the concentration profiles of Cs + and from the concentration profiles of I- in the blank samples. Finally, the effects of [Cs+] and [NaCl] on Kd-values for Cs+ were discussed from the viewpoint of adsorption by ion exchange and electrostatic attraction. The Kd-values were considered to be combined sorption by both reactions.
| Original language | English |
|---|---|
| Pages (from-to) | 597-602 |
| Number of pages | 6 |
| Journal | Materials Research Society Symposium Proceedings |
| Volume | 807 |
| Publication status | Published - Dec 1 2004 |
| Externally published | Yes |
| Event | Scientific Basis for Nuclear Waste Management XXVII - Kalmar, Sweden Duration: Jun 15 2003 → Jun 19 2003 |
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering