Hostname: page-component-7479d7b7d-jwnkl Total loading time: 0 Render date: 2024-07-15T04:11:17.591Z Has data issue: false hasContentIssue false
  • English
  • Français

Electrostatic forces Between Clay and Cations as Calculated and Inferred from Electrical Conductivity

Published online by Cambridge University Press:  01 July 2024

I. Shainberg  and
W. D. Kemper
I. Shainberg
Affiliation:
U.S. Department of Agriculture and Colorado State University, Fort Collins, Colorado
W. D. Kemper
Affiliation:
U.S. Department of Agriculture and Colorado State University, Fort Collins, Colorado
Get access Rights & Permissions [Opens in a new window]

Abstract

Equivalent conductivities of adsorbed cations were determined in clays saturated with Na+, Cs+, Ca++ and with mixtures of these cations. Measurements were also made on Ca++ clays which had been forced by previous drying into bundles of platelets or tac-toids. The average mobility of adsorbed Ca++ and Cs+ is much lower than that of adsorbed Na+.

It was concluded that the average mobility of adsorbed Ca++ is low because most of this Ca++ is on the internal surfaces of tactoids. Ca++ adsorbed between these internal surfaces appears to have a mobility much lower than Ca++ on the external surfaces which has a mobility of the same order of magnitude as Na+. Polarization of adsorbed Cs+ accounts at least partially for its low mobility in these clays.

Demixing of adsorbed cations (segregation with Na+ dominant between some platelets and Ca++ between others) is suggested as an initial step leading to breakup of a Na+-Ca++ clay mass into tactoids. The tactoid model, with Ca++ and Na+ preferentially on the internal and external surfaces respectively, furnishes an explanation of the instability of clay and soil aggregates with 15% exchangeable sodium.

Type
Research Article
Information
Clays and Clay Minerals , Volume 14 , February 1966 , pp. 117 - 132
Copyright
Copyright © Clay Minerals Society 1966

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.)

Footnotes

Contribution from the Northern Plains Branch, Soil and Water Conservation Research Division, Agricultural Research Service, USDA, and the Colorado Agricultural Experiment Station. Colorado Agricultural Experiment Station Scientific Journal Series 1063. Portions of this work were supported by the National Science Foundation and a Colorado State University Faculty Improvement Council Research Grant.

References

Babcock, K. L. (1963) Theory of the chemical properties of soil colloidal systems at equilibrium: Hilgardia 34, 417–542.CrossRefGoogle Scholar
Blackmore, A. V. and Miller, R. D. (1961) Tactoid size and osmotic swelling in calcium montmorillonite: Proc. Soil Sci. Soc. Amer. 25, 169–73.CrossRefGoogle Scholar
Bolt, G. H. (1955) Ion adsorption by clays: Soil Sci. 79, 267–76.CrossRefGoogle Scholar
Brown, G. (1961) (Ed.) The X-ray identification and crystal structures of clay minerals: Mineralogical Soc., London.Google Scholar
Eriksson, E. (1952) Cation exchange equilibria on clay minerals: Soil Sci., 74, 103113.CrossRefGoogle Scholar
Gast, R. G. and East, P. J. (1964) Potentiometric, electric conductivity and self- diffusion measurements in clay water systems: Clays and Clay Minerals, Proc. 12th Conf., Pergamon Press, New York, 297–310.Google Scholar
Glasstone, S., (1959) Text booh of physical chemistry: 2nd ed., D. Van Nostrand, Princeton, New Jersey.Google Scholar
Haggis, G. H., Hasted, J. V. and Buchanan, T. J. (1952) The dielectric properties of water in solutions: Jour. Chem. Phys. 20, 1452–65.Google Scholar
Howell, B. F. and Licastro, P. H. (1961) Dielectric behavior of rocks and minerals: Amer. Min. 46, 269.Google Scholar
Jacobs, D. G. (1965) The effect of lattice collapse of layer aluminosilicates on the sorption of Cs: Jour. Amer. Chem. Soc. (in press).Google Scholar
Kemper, W. D., Maasland, D. E. L. and Porter, L. K. (1964) Mobility of water adjacent to mineral surfaces: Soil Sci. Soc. Amer. Proc. 28, 164–7.CrossRefGoogle Scholar
Kruyt, H. R. (1952) Colloid Science, 1, Elsevier, Amsterdam.Google Scholar
Low, P. F. (1958) The apparent mobilities of exchangeable alkali metal cations in bentonite-water systems: Soil Sci. Soc. Amer. Proc. 22, 395–8.CrossRefGoogle Scholar
McAtee, J. L. (1956) Random interstratification in montmorillonite Am. Min., 41, 627–631.Google Scholar
McAtee, J. L. (1961) Heterogeneity in montmorillonites. Clays Clay Minerals, Proc. Natl. Conf. Clays Clay Minerals Fifth Conf. 1956, 279–288.Google Scholar
Norrish, K. and Quirk, J. P. (1954) Crystalline swelling of montmorillonite: Nature 173, 255–257.CrossRefGoogle Scholar
Shainberg, I. and Kemper, W. D. (1966a) Hydration status of adsorbed ions: Soil Sci. Soc. Amer. Proc. (in press).CrossRefGoogle Scholar
Shainberg, I. and Kemper, W. D. (1966b) Electrical conductivities of adsorbed alkali cations in bentonite water and bentonite alcohol system: Soil Sci. Soc. Amer. Proc. (in press).CrossRefGoogle Scholar
U.S. Salinity Laboratory Staff (1954) Diagnosis and improvement of saline and alkali soils: Agrie. Handbook No. 60, U.S.D.A.Google Scholar
Van Olphen, H. and Waxman, M. H. (1956) Surface conductance of sodium bentonite in water: Clays and Clay Minerals, Proc. 5th Conf. Nat. Acad. Sci.—Nat. Res. Council Pub. 566, 61–80.Google Scholar
Van Olphen, H. (1956) Forces between suspended bentonite particles. Part II. Calcium bentonite: Clays and Clay Minerals, Proc. 6th Conf., Pergamon Press, New York, 196–206.Google Scholar
Van Olphen, H. (1957) Surface conductance of various ion forms of bentonite in water and the electrical double layer: Jour. Phys. Chem., 61, 1276–80.CrossRefGoogle Scholar
Van Schaik, J. C., Kemper, W. D. and Olsen, S. R. (1965) Contribution of adsorbed cations to diffusion in clay water systems: Soil Sci. Soc. Amer. Proc. (in press).CrossRefGoogle Scholar
Warkentin, P. V., Bolt, G. H. and Miller, R. D. (1957) Swelling pressure of montmorillonite: Soil Sci. Soc. Amer. Proc. 21, 495–7.10.2136/sssaj1957.03615995002100050009xCrossRefGoogle Scholar