Effective diffusion coefficients(De) in bentonite were measured as a function of ionic charge to evaluate the degree of surface diffusion and anion exclusion. The De measurements for Ni2+, Sm3+ and Se3 2− were carried out for 1.8Mg•m−3 by through-diffusion method. Sodium bentonite, Kunigel-V1® was used. The order of obtained De values was Sm3+>Ni2+>SeO3 2−. These De values were compared with those reported to date. Consequently, the order of De values was Cs+>Sm3+>HTO>Ni2+>anions(I−, Cl−, CO3 2−, SeO3 2−, TcO4 −, NpO2CO3 −, UO2(CO3)3 4−), showing a tendency of cations>HTO>anions. The reason that the De of Ni2+ was lower than that of HTO may be because the free water diffusion coefficient(Do) of Ni2+ is about 1/3 of that of HTO. The formation factors(FF) were in the order, Sm3+>Cs+>Ni2+>HTO>anions, indicating a possibility of surface diffusion in cations and of anion exclusion in anions. In this case, the FF of Sm3+ was approximately 5 times greater than that of HTO. However, since the Do of Sm3+ is about 1/3 of that of HTO, the De of Sm3+ may have been a little higher than that of HTO. Based on this, it is presumed that surface diffusive effect on De in bentonite is insignificant.
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H. Sato, PNC TN8410 98-097, 1998.
H. Sato and T. Shibutani, PNC Technical Review No.91, PNC TN8410 94-284, 1994 (in Japanese).
A. Muurinen, P. Pentilä-Hiltunen, and J. Rantanen, in Scientific Basis for Nuclear Waste Management X, edited by J. K. Bates and W. B. Seefeldt Mater. Res. Soc. Proc. 84, Pittsburgh, PA, 1987) pp. 803–811.
S. C. Chung and M. N. Gray, in Scientific Basis for Nuclear Waste Management XI, edited by W. Lutze and R. C. Ewing Mater. Res. Soc. Proc. 127, Pittsburgh, PA, 1989) pp. 677–681.
D. W. Oscarson and M. N. Gray, Clay and Clay Minerals 42, 534 (1994).
J. W. Choi, D. W. Oscarson, and M. N. Gray, J. Contaminant Hydrology 22, 189 (1996).
A. Muurinen, P. Pentilä-Hiltunen, and K. Uusheimo, in Scientific Basis for Nuclear Waste Management XI, edited by W. Lutze and R. C. Ewing Mater. Res. Soc. Proc. 127, Pittsburgh, PA, 1989) pp. 743–748.
T. E. Eriksen and M. Jansson, SKB 96-16, 1996.
H. Kato, M. Muroi, N. Yamada, H. Ishida, and H. Sato, in Scientific Basis for Nuclear Waste Management XVIII, edited by T. Murakami and R. C. Ewing Mater. Res. Soc. Proc. 353, Pittsburgh, PA, 1995) pp. 277–284.
H. Kato, T. Nakazawa, and S. Ueta, in Scientific Basis for Nuclear Waste Management XX1I (Mater. Res. Soc. Proc. 556, in press).
Japan Nuclear Cycle Development Institute, JNC TN 1400 99-010, 1999.
M. Ito, M. Okamoto, M. Shibata, Y. Sasaki, T. Danbara, K. Suzuki, and T. Watanabe, PNC TN8430 93-003, 1993 (in Japanese).
M. Ito, M. Okamoto, K. Suzuki, M. Shibata, and Y. Sasaki, J. Atomic Energy Soc. Japan, 36 (11), 1055–1058 (1994)(in Japanese).
J. Crank, The Mathematics of Diffusion, 2nd ed. (Pergamon Press, Oxford, 1975).
K. Skagius and I. Neretnieks, KBS TR82-12, 1982.
H. Sato, T. Shibutani, and M. Yui, J. Contaminant Hydrology 26, 119 (1997).
R. A. Robinson and R. H. Stokes, Electrolyte Solutions, 2nd ed. (Butterworths, London, 1959). p. 317.
Y. Marcus, Ion Properties (Marcel Dekker, Inc., New York, 1997), pp. 168–170.
T. Shibutani, M. Yui, and H. Yoshikawa, in Scientific Basis for Nuclear Waste Management XVII, edited by A. Barkatt and R. A. Van Konynenburg Mater. Res. Soc. Proc. 333, Pittsburgh, PA, 1994) pp. 725–730.
S. Tajima, An Introduction to Electrochemistry, 3rd ed. ( Kyoritsu, Tokyo, 1986), p. 102 (in Japanese).
S. Shibutani, PNC Technical Review, No.97, PNC TN8410 96-011, 1996 (in Japanese).
D. G. Brookins, Eh-pH Diagrams for Geochemistry (Springer-Verlag, Berlin, 1988).
H. Sato and M. Yui, in Scientific Basis for Nuclear Waste Management XVIII, edited by T. Murakami and R. C. Ewing Mater. Res. Soc. Proc. 353, Pittsburgh, PA, 1995) pp. 269–276.
Chemical Society of Japan, Chemical Handbook, 4th ed. (Maruzen, Tokyo, 1993), p. 11-61 (in Japanese).
H. Sato, M. Yui, and H. Yoshikawa, J. Nucl. Sci. Tech., 33 (12), 950–955 (1996).
T. Yamaguchi, PNC TN 1100 96-010, 156–160, 1996 (in Japanese).
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Sato, H. Effect of Ionic Charge on Effective Diffusion Coefficient in Compacted Sodium Bentonite. MRS Online Proceedings Library 608, 267 (1999). https://doi.org/10.1557/PROC-608-267