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Low-Angle X-Ray Diffraction Studies of the Swelling of Montmorillonite and Vermiculite

Published online by Cambridge University Press:  01 January 2024

K. Norrish
Affiliation:
Commonwealth Scientific and Industrial Research Organization, Division of Soils, Adelaide, Australia
J. A. Rausell-Colom
Affiliation:
Commonwealth Scientific and Industrial Research Organization, Division of Soils, Adelaide, Australia

Abstract

Various workers have studied the mechanism of swelling of Na-montmorillonite and have demonstrated that its ability to swell is due to water penetrating between the individual silicate sheets. In the present study intraerystalline swelling was followed by diffraction techniques which enabled the movement of the silicate sheets with respect to one another to be measured as a function of electrolyte concentration, with or without an externally applied load. The observations have been made on oriented flakes of Na-montmorillonite and single crystals of Li-vermiculite.

Qualitatively the minerals behave similarly when swollen in salt solutions. They both show an initial stage of crystalline swelling, after which there is an explosive increase to the gel state, and then the distance apart of the silicate sheets increases linearly with C-½, where C is electrolyte concentration. Quantitatively, however, their swelling is very different, particularly after the “explosion”, where vermiculite generally gives higher spacings than montmorillonite. There are two other important differences in the swelling of montmorillonite and vermiculite. Firstly, while the swelling of vermiculite appears to be reversible both with respect to electrolyte concentration and applied pressure, the swelling of montmorillonite shows a marked hysteresis. Secondly, in montmorillonite, swelling depends very strongly on pH or chemical treatment.

There is little doubt that the development of diffuse “double layers” gives rise to repulsive forces, which cause the silicate sheets to move apart. Van der Waals’ forces have been regarded as providing attraction, but it is found that, at the observed interlayer separations, the magnitude of these attractive forces is inadequate to balance repulsion, both in montmorillonite and vermiculite.

The present results demonstrate that in vermiculite swelling proceeds until the interlayer separation causes the repulsion between sheets to drop to a value of ~ 2.5 × 104 dyn/cm2. This attractive force, which limits swelling, appears to be independent of sheet separation and electrolyte concentration. In montmorillonite swelling is opposed by edge-to-face bonds between sheets, whose number and strength can be controlled by chemical treatment. These bonds act to resist any displacement of the sheets, either swelling or contraction. This mechanism is compatible with the observed swelling behavior of montmorillonite, and explains the differences between the swelling of this mineral and that of vermiculite where, because the sheets are considerably larger, the force arising from edge-to-face bonds is small or absent.

Type
Symposium on Occurrence and Origin of Vermiculite
Copyright
Copyright © Clay Minerals Society 1961

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References

Aldrich, D. G. and Buchanan, J. R. (1958) Anomalies in techniques for preparing H-betonites: Soil Sci. Soc. Amer. Proc., v. 22, pp. 281285.CrossRefGoogle Scholar
Aylmore, L. A. G. and Quirk, J. P. (1962) The structural status of clay systems: Clays and, Clay Minerals, v. 9, Pergamon Press, New York, pp. 104130.CrossRefGoogle Scholar
Bates, T. F. and Comer, J. J. (1955) Electron microscopy of clay surfaces: Clays and Clay Minerals, Nat. Acad. Sci.-Nat. Res. Council, pub. 395, pp. 125.Google Scholar
Black, W., deJong, J. G. V., Overbeek, J. Th. G. and Sparnaay, M. J. (1960) Measurement of retarded van der Waals' forces: Trans. Faraday Soc., v. 56, pp. 15971608.CrossRefGoogle Scholar
Bolt, G. H. (1955) Analysis of the validity of the Gouy-Chapman theory of the electric double layer: J. Coll. Sci., v. 10, pp. 206218.CrossRefGoogle Scholar
Bolt, G. H. (1956) Physico-chemical analysis of the compressibility of pure clays: Geotechnique, v. 6, pp. 8693.CrossRefGoogle Scholar
Casimir, H. B. G. and Polder, D. (1948) The influence of retardation on the Londonvan der Waals' forces: Phys. Rev., v. 73, pp. 360372.CrossRefGoogle Scholar
Cowley, J. M. and Goswami, A. (1961) Electron diffraction patterns of montmorillonite: Acta Cryst., v. 14, pp. 10711079.CrossRefGoogle Scholar
Derjaguin, B. V., Titijevskaia, A. S., Abricossova, I. I. and Malkina, A. D. (1954) Investigation of the forces of interaction of surfaces in different media and their application to the problem of colloid stability: Disc. Faraday Soc., v. 18, pp. 2441. Also pp. 181 and following (General Discussion).CrossRefGoogle Scholar
Foster, W. K., Savins, J. G. and Waite, J. M. (1955) Lattice expansion and rheological behaviour relationships in water—montmorillonite systems: Clays and Clay Minerals, Nat. Acad. Sci.-Nat. Res. Council, pub. 395, pp. 296316.Google Scholar
Garrett, W. G. and Walker, G. F. (1962) Swelling of some vermieulite-organic complexes in water: Clays and Clay Minerals, v. 9, Pergamon Press, New York, pp. 557567.CrossRefGoogle Scholar
Guinier, A. and Fournet, G. (1955) Small-angle Scattering of X-rays: John Wiley, New York, 268 pp.Google Scholar
Hight, R. (1962) A small angle X-ray scattering study of some montmorillonite clay systems: Doctoral thesis, University of Missouri.CrossRefGoogle Scholar
Howe, P. G., Benton, D. P. and Puddington, I. E. (1955) London-van der Waals' attractive forces between glass surfaces: Ganad. J. Chem., v. 33, pp. 13751383.Google Scholar
James, R. W. (1948) The Optical Principles of the Diffraction of X-rays: G. Bell, London, 623 pp.Google Scholar
Mathieson, A. McL. and Walker, G. F. (1954) Crystal structure of magnesium- vermiculite: Amer. Min., v. 39, pp. 231255.Google Scholar
Nash, V. E. (1960) Role of exchangeable cations in viscosity of clay suspensions: Clays and Clay Minerals, 7th Conf., Pergamon Press, New York, pp. 328342.Google Scholar
Norrish, K. (1954) The swelling of montmorillonite: Disc. Faraday Soc., no. 18, pp. 120134.CrossRefGoogle Scholar
Overbeek, J. Th. G. and Sparnaay, M. J. (1954) London-van der Waals' attraction between macroscopic objects: Disc. Faraday Soc., no. 18, pp. 1224.CrossRefGoogle Scholar
Rausell-Colom, J. A. (1958) El hinchamiento de la montmorillonita-sodica y del complejo montmorillonita-krilium en electrolitos: Doctoral thesis, Univ. of Madrid.Google Scholar
Rausell-Colom, J. A. (1962) Correction of small-angle X-ray diffraction measurements for the influence of beam height. Case of specimen having preferred orientation of particles: In preparation.CrossRefGoogle Scholar
Rausell-Colom, J. A. and Norrish, K. (1962) Low-angle diffractometer for studying the swelling of clay minerals. Brit. J. Sci. Instr., v. 39, pp. 156159.CrossRefGoogle Scholar
Schofield, R. K. (1947) Calculation of surface areas from measurements of negative adsorption: Nature, v. 160, pp. 408410.CrossRefGoogle Scholar
Schofield, R. K. and Samson, H. R. (1954) Flocculation of kaolinite due to the attraction of oppositely charged crystal faces: Disc. Faraday Soc., no. 18, pp. 135145.CrossRefGoogle Scholar
van Olphen, H. (1950) Stabilisation of montmorillonite sols by chemical treatment. Part II: Effect of polymetaphosphates, sodium metasilicate, oxalate, citrate and orthophosphate on Na and Ca montmorillonite sols: Bee. Trav. Chem. Pays Bas., v. 69, pp. 13081322.CrossRefGoogle Scholar
van Olphen, H. (1951) Rheological phenomena of clay sols in connection with the charge distribution of the micelles: Disc. Faraday Soc., no. 11, pp. 8284.CrossRefGoogle Scholar
van Olphen, H. (1954) Interlayer forces in bentonite: Clays and Clay Minerals, Nat. Acad. Sci.-Nat. Res. Council, pub. 327, pp. 418438.Google Scholar
van Olphen, H. (1956) Forces between suspended bentonite particles: Clays and Clay Minerals, Nat. Acad. Sci.-Nat. Res. Council, pub. 456, pp. 204224.Google Scholar
van Olphen, H. (1961) Unit layer interaction in hydrous montmorillonite systems; Shell Development Co. Expl. and Prod. Res. Div. pub. 273, pp. 114.Google Scholar
Verwey, E. J. W. and Overbeek, J. Th. G. (1948) Theory of the Stability of Lyophobic Colloids: Elsevier, New York, 205 pp.Google Scholar
Walker, G. F. (1960) Macroscopic swelling of vermiculite crystals in water: Nature, v. 187, p. 312.CrossRefGoogle Scholar
Walker, G. F. and Milne, A. (1950) Hydration of vermiculite saturated with various cations: Trans, 4th Int. Congress Soil Sci., v. 2, pp. 6267.Google Scholar
Warkentin, B. P. and Schofield, R. K. (1960) Swelling pressures of dilute Na-montmorillonite pastes: Clays and Clay Minerals, 7th Conf., Pergamon Press, New York, pp. 343349.Google Scholar