Clays and Clay Minerals

, Volume 40, Issue 3, pp 287–291 | Cite as

Electroacoustic Study of Adsorption of Cetylpyridinium Chloride on Kaolinite

  • William N. Rowlands
  • Robert J. Hunter


Adsorption of cetylpyridinium chloride (CPC) onto kaolinite can be followed using the electroacoustic effect. The dynamic mobility, measured at a frequency of 1 MHz, varies from about −2 to +1 × 10−8 m2 V−1 s−1 in a number of steps, reflecting the adsorption of two separate layers, with the bilayer being more obvious, especially at pH 5–8. The behaviour at different pHs reflects the different charge characteristics of the basal cleavage planes and the crystal edges. When the amount of added CPC is equal to the cation exchange capacity of the clay, the kinetic charge changes from negative to positive and there is a pronounced break in the conductivity curve. It is also possible to estimate the edge to face area from such measurements and so obtain a measure of the aspect ratio of the clay crystallites. The (minimum) value for this clay is about 5:1.

Key Words

Electroacoustics Adsorption Cetylpyridinium ion Kaolin Electrokinetics Dynamic mobility 


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  1. Babchin A. J., Chow, R. S., and Sawtasky R. P. (1989) Electrokinetic measurements by electroacoustic methods: Adv. Colloid Interface Sci. 30, 111–151.CrossRefGoogle Scholar
  2. Chhabra R., Pleysier J., and Cremers C. (1975) Measurement of the cation exchange capacity and exchangeable cations in soils: A new method: in Proc. Int. Clay Conf., Mexico City, S. W. Bailey, ed., Applied Publishing, Wilmette, Illinois, 439–449.Google Scholar
  3. Greenland D. J. and Quirk J. P. (1962) Surface areas of soil colloids: Trans. Int. Soil Cong. New Zealand, 3–10.Google Scholar
  4. Greenland D. J. and Quirk J. P. (1963) Determination of surface areas by adsorption of cetylpyridinium bromide from aqueous solution: J. Phys. Chem. 67, 2886–2887.CrossRefGoogle Scholar
  5. Hayter J. B. and Hunter R. J. (1972) Adsorption of quaternary ammonium ions at the mercury solution interface. Part I. The integral capacity and the structure of the adsorbed film: Electroanal. Chem. and Interfacial Electrochem. 37, 71–80.CrossRefGoogle Scholar
  6. Kunyima B., Viaene K., Hassan Khalil M. M., Schoonheydt R. A., Crutzen M., and De Schryver F. C. (1990) Study of the adsorption and polymerization of functionalized organic ammonium derivatives on a clay surface: Langmuir 6, 482–486.CrossRefGoogle Scholar
  7. O’Brien R. W. (1988) Electroacoustic effects in a dilute suspension of spherical particles: J. Fluid Mech. 190, 71–86.CrossRefGoogle Scholar
  8. O’Brien R. W., Midmore B. R., Lamb A., and Hunter R. J. (1991) Electroacoustic studies of moderately concentrated colloidal suspensions: Faraday Disc. Chem. Soc. 90, 301–312.CrossRefGoogle Scholar
  9. Posner A. M. and Quirk J. P. (1964) Adsorption of water from concentrated electrolyte solutions by montmorillonite and illite: Proc. Roy. Soc. (London) A278, 35–56.Google Scholar
  10. Slade P. G., Raupach M., and Emerson W. W. (1978) The ordering of cetylpyridinium bromide on vermiculite: Clays & Clay Minerals 26, 125–134.CrossRefGoogle Scholar
  11. Welzen J. T. A. M., Stein H. N., Stevels J. M., and Siskens C. A. M. (1980) The influence of surface-active agents on kaolinite: J. Colloid Interface Sci. 81, 455–467.CrossRefGoogle Scholar
  12. Wierer K. A. and Dobias B. (1988) Adsorption of surfactants at the kaolinite-water interface: A calorimetric study: Prog. Colloid Polym. Sci. 76, 283–285.CrossRefGoogle Scholar

Copyright information

© The Clay Minerals Society 1992

Authors and Affiliations

  • William N. Rowlands
    • 1
  • Robert J. Hunter
    • 1
  1. 1.School of ChemistryUniversity of SydneyAustralia

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