Hostname: page-component-77c89778f8-vsgnj Total loading time: 0 Render date: 2024-07-24T23:44:54.151Z Has data issue: false hasContentIssue false

Diffusion of Cesium and Iodine in Compacted Sodium Montmorillonite Under Different Saline Conditions

Published online by Cambridge University Press:  15 February 2011

Yukio Tachi
Affiliation:
Geological Isolation Research and Development Directorate, Japan Atomic Energy Agency 4-33 Muramatsu, Tokai-mura, Ibaraki 319-1194, Japan
Kenji Yotsuji
Affiliation:
Geological Isolation Research and Development Directorate, Japan Atomic Energy Agency 4-33 Muramatsu, Tokai-mura, Ibaraki 319-1194, Japan
Yoshimi Seida
Affiliation:
Geological Isolation Research and Development Directorate, Japan Atomic Energy Agency 4-33 Muramatsu, Tokai-mura, Ibaraki 319-1194, Japan
Mikazu Yui
Affiliation:
Geological Isolation Research and Development Directorate, Japan Atomic Energy Agency 4-33 Muramatsu, Tokai-mura, Ibaraki 319-1194, Japan
Get access

Abstract

Diffusion and sorption of cesium (Cs) and iodine (I) were investigated in a purified and moderately compacted sodium montmorillonite (dry density of 800 kg m-3) saturated with 0.01, 0.1 and 0.5M NaCl solutions. The effective diffusivity (De) and capacity factor (α) for Cs and I were measured by through-diffusion experiments, coupled with multiple curve analyses, including tracer depletion, breakthrough and depth concentration curves, which could be fitted with a conventional diffusion model using only one set of parameters. The De values obtained for Cs were of the order of 10-9-10-10 m2 s-1 and decreased as salinity increased, and those for I were of the order of 10-11-10-12 m2 s-1 and showed the opposite dependency. The distribution coefficient (Kd) of Cs decreased from the order of 100 to 10-2 m3 kg-1 as salinity increased. Diffusion and sorption parameters for Cs were also obtained by in-diffusion and batch sorption experiments and showed good agreement with those obtained by the through-diffusion experiments. The diffusion model, based on homogeneous pore structure and electrical double layer (EDL) theory, predicted the salinity dependence of De reasonably well, showing the effect of cation excess and anion exclusion as a function of salinity. The apparent diffusivity (Da), which includes sorption effects, was also interpreted by a coupled sorption model.

Type
Research Article
Copyright
Copyright © Materials Research Society 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1 Muurinen, A., Doctoral Thesis, VTT Publications 168, Espoo, Finland (1994)Google Scholar
2 Ochs, M., Lothenbach, B., Wanner, H., Sato, H. and Yui, M., J. Contam. Hydrol. 47, 283 (2001).Google Scholar
3 Lehikoinen, J., Muurinen, A., Valkiainen, M., Scientific Basis for Nuclear Waste Management XXII, edited by Wronkiewicz, D.J., Lee, J.H., (Mater. Res. Soc. Proc., 556) 663 (1999).Google Scholar
4 Molera, M. and Eriksen, T., Radiochim. Acta 90, 753 (2002).Google Scholar
5 Glaus, M.A., Baeyens, B., Bradbury, M.H., Jakob, A., Loon, L.R. Van and Yaroshchuk, A., Environ. Sci. Technol. 41, 478 (2007).Google Scholar
6 Kozaki, T., Liu, J. and Sato, S., Phys. Chem. Earth 33, 957 (2008).Google Scholar
7 Molera, M., Eriksen, T. and Jansson, M., Appl. Clay Sci. 23, 69 (2003).Google Scholar
8 Loon, L.R. Van, Glaus, M.A. and Müller, W., Appl. Geochem. 22, 2536 (2007).Google Scholar
9 Tachi, Y., Seida, Y., Doi, R., Xia, X. and Yui, M., Scientific Basis for Nuclear Waste Management XXXII, edited by Rebak, R.B., Hyatt, N.C., Pickett, D.A., (Mater. Res. Soc. Proc., 1124) (2009) (in press).Google Scholar
10 Suzuki, S., Sato, H. and Tachi, Y., J. Nucl. Sci. Tech. 40(9), 698 (2003).Google Scholar
11 Suzuki, S., Haginuma, M. and Suzuki, K., J. Nucl. Sci. Tech. 44(1), 81 (2007).Google Scholar
12 Zhang, M., Takeda, M. and Nakajima, H., Scientific Basis for Nuclear Waste Management XXIX, edited by Iseghem, P. Van, (Mater. Res. Soc. Proc., 932) 135 (2006).Google Scholar
13 Sato, H., Ashida, T., Kohara, Y., Yui, M. and Sasaki, N., J. Nucl. Sci. Tech. 29(9), 873 (1992).Google Scholar
14 Wanner, H., Albinsson, Y. and Wieland, E., Fresenius, , J. Anal. Chem. 354, 763 (1996).Google Scholar
15 Parkhurst, D.L. and Appelo, C.A.J., User's Guide to PHREEQC (ver.2), USGS Report 994259 (1999).Google Scholar
16 Shainberg, I. and Kemper, W.D., Clays Clay Miner. 14(1), 117 (1966).Google Scholar
17 Takahashi, M., Doctoral Thesis, The University of Tokyo, Japan (1989)Google Scholar
18 Kato, H., Muroi, M., Yamada, N., Ishida, H. and Sato, H., Scientific Basis for Nuclear Waste Management XVIII, edited by Murakami, T., Ewing, R.C., (Mater. Res. Soc. Proc., 353) 277 (1995).Google Scholar
19 Sherwood, T.K., Pigford, R.L., Wilke, C.R., Mass Transfer, McGraw-Hill, New York (1975).Google Scholar
20 Verwey, E.J.W. and Overbeek, J.Th.G., Theory of the Stability of Lyophobic Colloids, Elsevier, Amsterdam (1948).Google Scholar
21 Low, P.F., Soil Sci. Soc. Am. J. 40, 500 (1976).Google Scholar