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Ordered Interstratification of Dehydrated and Hydrated Na-Smectite

Published online by Cambridge University Press:  02 April 2024

D. M. Moore  and
John Hower
D. M. Moore
Affiliation:
Knox College, Galesburg, Illinois 61401
John Hower
Affiliation:
Department of Geology, University of Illinois, Urbana, Illinois 61801
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Abstract

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The 001 spacing of Na-smectite was found to vary from 9.6 Å at 0% relative humidity (RH) to 12.4 Å at 60-65% RH. The 9.6-Å spacing corresponds to dehydrated Na-smectite, and the 12.4-Å corresponds to Na-smectite with one water layer. A regular series of intermediate values resulted from ordered interstratification of the 9.6- and 12.4-Å units. Ordered interstratification was confirmed by the presence of a 001 spacing of 9.6 + 12.4 Å = 22 Å. This peak appeared under experimental conditions at about 35% RH. It appeared for calculated simulations of ordered stacking of 50/50 mixtures (±10%) of 9.6- and 12.4-Å units. The 004 peak of this 22-Å spacing interacted with the 002 of the 9.6-Å spacing of ordered mixtures of more than 50% 9.6-Å units and with the 002 of the 12.4-Å spacing of ordered mixtures of more than 50% 12.4-Å units. The result of this interaction was a complex peak, the position of which was a function of the ratio of 9.6- and 12.4-Å units. This complex peak was noted for experimental and for calculated conditions. Calculated tracings assuming ordered stacking matched the experimental tracings closely, whereas those assuming random stacking did not.

Ordering was apparently due to the interaction of the positive charge of the interlayer cation repelling the positive charge of the hydrogens of the hydroxyl ions, one above and one below, closest to the interlayer space. The collapse of a single interlayer space (dehydration) brought the interlayer cation closer to the hydrogens of the hydroxyls causing the hydroxyls to rotate such that the hydrogens shifted toward the adjacent interlayer spaces. Collapse of these two interlayer spaces was therefore more difficult. This same mechanism helps explain ordering in illite/smectite. The difference is that hydration/dehydration is quick and reversible, whereas the change from smectite to illite is slow and irreversible.

Keywords

HydrationHydrogen positionsIlliteInterstratificationSmectiteWaterX-ray powder diffraction
Type
Research Article
Information
Clays and Clay Minerals , Volume 34 , Issue 4 , August 1986 , pp. 379 - 384
Copyright
Copyright © 1986, The Clay Minerals Society

Footnotes

†

Deceased.

References

Bassett, W. A., 1959 The origin of the vermiculite deposit at Libby, Montana Amer. Mineral. 44 282–299.Google Scholar
Bradley, W. F., Grim, R. E. and Clark, G. F., 1937 A study of the behavior of montmorillonite on wetting Z. Kristallogr. 97 260–270.Google Scholar
Giese, R. F. Jr., 1971 Hydroxyl orientation in muscovite indicated by electrostatic energy calculations Science 172 263–264.CrossRefGoogle ScholarPubMed
Giese, R. F. Jr., 1977 The influence of hydroxyl orientation, stacking sequence, and ionic substitution on the interlayer bonding of micas Clays & Clay Minerals 25 102–104.CrossRefGoogle Scholar
Giese, R. F. Jr., 1979 Hydroxyl orientations in 2:1 phyllosilicates Clays & Clay Minerals 27 213–223.CrossRefGoogle Scholar
Giese, R. F. Jr., 1980 Hydroxyl orientations and interlayer bonding in amesite Clays & Clay Minerals 28 81–86.CrossRefGoogle Scholar
Giese, R. F. Jr. and Datta, P., 1973 Hydroxyl orientations in the muscovite polymorphs 2M1, 3T and 1M: Z. Kristallogr. 137 436–438.Google Scholar
Glaeser, R. and Méring, J., 1968 Homogeneous hydration domains of the smectites C.R. Hebd. Séanc. Acad. Sci. Paris 246 436–466.Google Scholar
Hendricks, S. B., Nelson, R. A. and Alexander, L. T., 1940 Hydration mechanism of the clay mineral montmorillonite saturated with various cations J. Amer. Chem. Soc. 62 1457–1464.CrossRefGoogle Scholar
Keren, R. and Shainberg, I., 1975 Water vapor isotherms and heat of immersion of Na/Ca-montmorillonite systems—I: homoionic clay Clays & Clay Minerals 23 193–200.CrossRefGoogle Scholar
Keren, R. and Shainberg, I., 1979 Water vapor isotherms and heat of immersion of Na/Ca-montmorillonite systems—II: mixed systems Clays & Clay Minerals 27 145–151.CrossRefGoogle Scholar
Keren, R. and Shainberg, I., 1980 Water vapor isotherms and heat of immerson of Na- and Ca-montmorillonite systems. III: thermodynamics Clays & Clay Minerals 28 204–210.CrossRefGoogle Scholar
MacEwan, D. M. C., Wilson, M. J., Brindley, G. W. and Brown, G., 1980 Interlayer and intercalation complexes of clay minerals Crystal Structure of Clay Minerals and Their X-ray Identification London Mineralogical Society 197–248.CrossRefGoogle Scholar
Mooney, R. W., Keenan, A. C. and Wood, L. A., 1952 Absorption of water vapour by montmorillonite J. Amer. Chem. Soc. 74 1367–1374.CrossRefGoogle Scholar
Nagelschmidt, G., 1936 The structure of montmorillonite Z. Kristallogr. 93 481–487.CrossRefGoogle Scholar
Reynolds, R. C. Jr., 1965 An X-ray study of an ethylene glycol-montmorillonite complex Amer. Mineral. 50 990–1001.Google Scholar
Reynolds, R. C. Jr. and Hower, J., 1970 The nature of interlayering in mixed-layer illite-montmorillonite Clays & Clay Minerals 18 25–36.CrossRefGoogle Scholar
Ross, C. S. and Shannon, E. V., 1926 Minerals of bentonite and related clays, and their physical properties J. Amer. Ceram. Soc. 9 77–96.CrossRefGoogle Scholar
Sawhney, B. L. and Bailey, S. W., 1967 Interstratification in vermiculite Clays & Clay Minerals, Proc. 15th Natl. Conference, Pittsburgh, Pennsylvania, 1966 New York Pergamon Press 75–84.Google Scholar
Walker, G. F., 1956 The mechanism of dehydration of Mg-vermiculite Natl. Acad. Sci.-Natl. Res. Council, Publ. 456 101–115.Google Scholar