Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-10T11:21:37.305Z Has data issue: false hasContentIssue false
  • English
  • Français

Cation Exchange Capacity of Kaolinite

Published online by Cambridge University Press:  28 February 2024

Chi Ma  and
Richard A. Eggleton
Chi Ma*
Affiliation:
Cooperative Research Center for Landscape Evolution and Mineral Exploration, Department of Geology, Australian National University, Canberra, ACT 0200, Australia
Richard A. Eggleton
Affiliation:
Cooperative Research Center for Landscape Evolution and Mineral Exploration, Department of Geology, Australian National University, Canberra, ACT 0200, Australia
*
†Present address: Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Experimental cation exchange capacities (CEC) of kaolinites were determined and compared to theoretical calculations of CEC. The comparison reveals that the exchangeable cations occur mostly on the edges and on the basal (OH) surfaces of the mineral. It also shows that permanent negative charge from isomorphous substitution of Al3+ for Si4+ is insignificant. The CEC of kaolinite strongly depends on the particle size (both thickness and diameter in the (00l plane) and pH value. Particle size is more important than crystallinity in affecting kaolinite CEC. This study shows that the hydroxyls on the exposed basal surfaces may be ionizable in aqueous solutions. The amount of negative charge on the edges and the exposed basal hydroxyls depends on pH and other ion concentrations. A higher pH value gives rise to more negative charges, which lead to a higher CEC value. This study indicates that charge from broken edges and exposed OH planes rather than charge from Al/Si substitution determines the kaolinite CEC, even at zero point charge. A high CEC in some kaolinites is found to be due to smectite layers on the surface of the kaolinite crystals.

Keywords

Cation Exchange CapacityEdgesExposed (OH) PlanesKaoliniteSubstitutionSurface Charge
Type
Research Article
Information
Clays and Clay Minerals , Volume 47 , Issue 2 , April 1999 , pp. 174 - 180
Copyright
Copyright © 1999, The Clay Minerals Society

References

Bailey, S.W., Brindley, G.W. and Brown, G., 1984 Structures of layer silicates Crystal Structures of Clay Minerals and Their X-ray Identification London Mineralogical Society 1–124.Google Scholar
Bain, D.C. Smith, B.F.L. and Wilson, M.J., 1987 Chemical analysis A Handbook of Determinative Methods in Clay Mineralogy Glasgow Blackie 301–320.Google Scholar
Bolland, M.D.A. Posner, A.M. and Quirk, J.P., 1976 Surface charge on kaolinites in aqueous suspension Australian Journal of Soil Research 14 197–216 10.1071/SR9760197.CrossRefGoogle Scholar
Brown, G. Brindley, G.W., Brindley, G.W. and Brown, G., 1984 X-ray diffraction procedure for clay mineral identification Crystal Structures of Clay Minerals and Their X-ray Identification London Mineralogical Society 305–360.Google Scholar
Churchman, G.W. Slade, P.G. Self, P.G. and Janik, L.J., 1994 Nature of interstratified kaolin-smectites in some Australian soils Australian Journal of Soil Research 32 805–822 10.1071/SR9940805.CrossRefGoogle Scholar
Ferris, A.P. and Jepson, W.B., 1975 The exchange capacities of kaolinite and the preparation of homoionic clays Journal of Colloid Interface Science 51 245–259 10.1016/0021-9797(75)90110-1.CrossRefGoogle Scholar
Grim, R.E., 1968 Clay Mineralogy New York McGraw-Hill.Google Scholar
Kim, Y. Kirkpatrick, R.J. and Cygan, R.T., 1996 Cs-133 NMR study of cesium of the surfaces of kaolinite and illite Geochimica et Cosmochimica Acta 60 4059–4074 10.1016/S0016-7037(96)00257-8.CrossRefGoogle Scholar
Ma, C., 1996 The ultra-structure of kaolin Canberra, Australia Australian National University.Google Scholar
McBride, M.B., 1976 Origin and position of exchange sites in kaolinite: As ESR study Clays and Clay Minerals 24 88–92 10.1346/CCMN.1976.0240207.CrossRefGoogle Scholar
McBride, M.B., Dixon, J.B. and Weed, S.B., 1989 Surface chemistry of soil minerals Minerals in Soil Environments (2nd edition) Madison, Wisconsin Soil Science Society of America 35–88.Google Scholar
Rand, B. and Melton, I.E., 1977 Particle interactions in aqueous kaolinite suspensions, I. Effect of pH and electrolyte upon the mode of particle interaction in homoionic sodium kaolinite suspensions Journal of Colloid Interface Science 60 308–320 10.1016/0021-9797(77)90290-9.CrossRefGoogle Scholar
Schindler, P.W. Stumm, W. and Stumm, W., 1987 The surface chemistry of oxides, hydroxides, and oxide minerals Aquatic Surface Chemistry New York Wiley Interscience 83–110.Google Scholar
Schofield, R.K. and Samson, H.R., 1953 The deflocculation of kaolinite suspensions and the accompanying change over from positive to negative chloride adsorption Clay Minerals Bulletin 2 45–51 10.1180/claymin.1953.002.9.08.CrossRefGoogle Scholar
Sposito, G., 1984 The Surface Chemistry of Soils New York Oxford University Press.Google Scholar
van Olphen, H., 1977 Clay Colloid Chemistry, 2nd edition New York John Wiley & Sons.Google Scholar
Wieland, E. and Stumm, W., 1992 Dissolution kinetics of kaolinite in acidic aqueous solution at 25°C Geochimica et Cosmochimica Acta 56 3339–3355 10.1016/0016-7037(92)90382-S.CrossRefGoogle Scholar
Williams, D.J.A. and Williams, K.P., 1978 Electrophoresis and zeta potential of kaolinite Journal of Colloid Interface Science 65 79–87 10.1016/0021-9797(78)90260-6.CrossRefGoogle Scholar
Zhou, Z. and Gunter, W.D., 1992 The nature of the surface charge of kaolinite Clays and Clay Minerals 40 365–368 10.1346/CCMN.1992.0400320.CrossRefGoogle Scholar