Abstract
The electrical conductivity of a colloid-water-electrolyte system increases with the frequency of the applied alternating electric current. The phenomenon is referred to as conductivity dispersion. This paper reports on the effects of electrolyte type, electrolyte concentration, and water content on the dispersion characteristics of kaolinite, illite, and silty clay soils, with emphasis on the mechanisms governing the dispersion phenomenon. It was observed that magnitude of conductivity dispersion increases with a reduction in water content, electrolyte concentration, and cation-exchange capacity of the clay. The type of ions influence the electrical dispersion through their size and mobility. Frequency effect increases as the hydrated radius of the counterions associated with the clay surface increases. Conductivity dispersion is explained primarily in terms of counterion/co-ion ratio in the diffuse double layer. Increase in the ratio of counterions to co-ions is an indication of a larger contribution to conduction by counterions than by co-ions, which in turn results in a larger frequency effect. Although diffusion coupling has an important role in the electrical dispersion characteristics of clay—water—electrolyte systems, other coupling phenomena, particularly electro-osmotic coupling, plays a significant part.
Similar content being viewed by others
References
Arulanandan, K. (1969) Hydraulic and electrical flows in clays: Clay & Clay Minerals 17, 63.
Arulanandan, K. (1966) Electrical response characteristics of clays and their relationship to soil structure: Ph.D. thesis, University of California, Berkeley.
Arulanandan, K. and Mitchell, J. K. (1968) Low frequency dielectric dispersion of clay-water-electrolyte systems: Clays & Clay Minerals 16, 337.
Babcock, K. L. (1963) Theory of the chemical properties of soil colloidal systems at equilibrium: Hilgardia 34 (11), 417.
Cole, K. S. and Curtis, H. J. (1937) Wheatstone bridge and electrolyte resistor for impedance measurements over a wide frequency range: Rev. Sci. Instr. 8, 333.
Donnan, F. G. (1924) The theory of membrane equilibria: Chem. Rev. 1, 73.
Esrig, M. I. (1964) Report of a feasibility study of electro-kinetic processes for stabilization of soils for military purposes: Research Report No. 1, School of Civil Engineering, Cornell University, Ithaca, New York.
Fraser, D. C., Keevil, N. B., Jr., and Ward, S. H. (1964) Conductivity spectra of rocks from the Craigmont ore environment: Geophysics 29, 832.
Gray, D. H. (1966) Coupled flow phenomena in clay-water systems: Ph.D. thesis, University of California, Berkeley.
Helfferich, F. (1962) Ion Exchange: McGraw-Hill, New York.
Henkel, J. H. and Van Nostrand, R. G. (1957) Experiments in induced polarization: Mining Engng. AIME Trans. 9, 355.
Juda, W. and McRae, W. R. (1953) U.S. Patent 2,636,851.
Kirda, C., Biggar, J. W. and Nielsen, D. R. (1973) Relative flow of salt and water in saturated and unsaturated soil: Paper presented before Soil Physics Division of the American Society of Agronomy, Las Vegas, Nevada, 12 November.
Marshall, D. J. and Madden, T. R. (1959) Induced polarization; a study of its causes: Geophysics 24, 790.
Mitchell, J. K. and Arulanandan, K. (1968) Electrical dispersion in relation to soil structure: Soil Mech. & Found. Am. Soc. Civil Engng. Proc. 94 (SM2), 447–471.
Mokady, R. S. and Low, P. F. (1966) Electrochemical determination of diffusion coefficients in clay-water systems: Soil Sci. Soc. Am. Proc. 30, 438.
Olsen, H. W. (1961) Hydraulic flow through saturated clays: Ph.D. Thesis, Massachusetts Institute of Technology, Cambridge, MA.
Schwan, H. P. (1963) Determination of biological impedances: Physical Techniques in Biological Research, Vol. 6, Academic Press, New York.
Schwan, H. P., Schwarz, G., Maczuk, J. and Pauly, H. (1962) On the low frequency dielectric dispersion of colloidal particles in electrolyte solution: J. Phys. Chem. 66, 2626.
Schwarz, G. (1962) A theory of low frequency dielectric dispersion of colloidal particles in electrolyte solution: J. Phys. Chem. 66, 2636.
Selig, E. T. and Mansukhani, S. (1975) Relationship of soil moisture to the dielectric property: Geotech. Engng. Div. Am. Soc. Civil Engng. Proc. 101 (GT8), 755.
Shainberg, I. and Kemper, W. D. (1966) Hydration status of adsorbed cations: Soil Sci. Soc. Am. Proc. 30, 707.
Spiegler, K. S. (1958) Transport processes in ionic membranes: Trans. Faraday Soc. 54, 1408.
Spiegler, K. S. and Arulanandan, K. (1967) Radiofrequency measurements of ion exchange membranes: Research and Development Report No. 353, U.S. Government Printing Office, Washington, D.C.
Vacquier, V., Holmes, C. R., Kintzinger, P. R. and Lavergne, M. (1957) Prospecting for ground water by induced electrical polarization: Geophysics 22, 660.
Waxman, M. H. and Smits, L. J. M. (1968) Electrical conductivities in oil-bearing shaly sands: Soc. Pet. Eng. J. 8 (2), 107.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Mehran, M., Arulanandan, K. Low Frequency Conductivity Dispersion in Clay-Water-Electrolyte Systems. Clays Clay Miner. 25, 39–48 (1977). https://doi.org/10.1346/CCMN.1977.0250107
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1346/CCMN.1977.0250107