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Effects of Iron Oxidation State on the Texture and Structural Order of Na-Nontronite Gels

Published online by Cambridge University Press:  02 April 2024

Joseph W. Stucki  and
Daniel Tessier
Joseph W. Stucki
Affiliation:
Department of Agronomy, University of Illinois, Urbana, Illinois, 61801
Daniel Tessier
Affiliation:
Station de Science du Sol, INRA, Route de Saint Cyr, 78026 Versailles, France
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Abstract

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Aqueous gels of unaltered (oxidized) and chemically reduced ferruginous smectite (SWa-1 from the Source Clays Repository of The Clay Minerals Society) were characterized by transmission electron microscopy, electron diffraction, and energy-dispersive X-ray fluorescence to establish details regarding their texture, inter-layer and inter-particle arrangements, and chemical composition. Micrographs revealed that the reduction of structural Fe(III) to Fe(II) caused a consolidation of smectite particles from an extensive network of small crystals (1–6 layers thick) to distinct particles of limited size in the a-b direction and about 20–40 layers thick. The interlayer distances in the reduced sample appeared to be more uniform than in the oxidized sample, but both exhibited spacings of about 12.6 A. Chemical analysis showed no qualitative differences as a result of oxidation state. Electron diffraction patterns displayed marked differences. The pattern of the oxidized sample consisted of homogeneous rings, indicating that the stacking order in the a-b plane was turbostratic or disordered, whereas the reduced pattern exhibited much more order as evidenced by distinct spots amid low-intensity rings, suggesting that inter-layer attractive forces were stronger if Fe(II) was present in the clay crystal.

Keywords

Electron diffractionFerric ironFerrous ironHigh-resolution transmission electron microscopyLayer structureNontronite
Type
Research Article
Information
Clays and Clay Minerals , Volume 39 , Issue 2 , April 1991 , pp. 137 - 143
Copyright
Copyright © 1991, The Clay Minerals Society

References

Annabi-Bergaya, F., Cruz, M. I., Gatineau, L. and Fripiat, J. J., 1980 Adsorption of alcohols by smectites. Role of exchangeable cations Clay Miner. 15 219 – 233.CrossRefGoogle Scholar
Ben Rhaïem, H., Pons, C.H. Tessier, D., Schultz, L. G., van Olphen, H. and Mumpton, F. A., 1987 Factors affecting the microstructure of smectites: Role of cation and history of applied stresses Proc. Int. Clay Conf. Denver, 1985 Bloomington, Indiana The Clay Minerals Society 292 – 297.Google Scholar
Brindley, G. W., MacEwan, D. M. C., Green, A. T. and Stewart, G. H., 1953 Structural aspects of the mineralogy of clays and related silicates Ceramics: A Symposium London The British Ceramic Society 15 – 59.Google Scholar
de la Calle, C., Dubernat, J., Suquet, H., Pezerat, H., Gaultier, J. P., Mamy, J. and Bailey, S. W., 1976 Crystal structure of two layer Mg-vermiculites and Na-, Ca-vermiculites Proc. Int. Clay Conf, Mexico City, 1975 Illinois Applied Publishing, Wilmette 201 – 209.Google Scholar
de la Calle, C., Suquet, H. and Pons, C. H., 1988 Stacking order in a 14.30-Å Mg-vermiculite Clays & Clay Minerals 36 481 – 490.CrossRefGoogle Scholar
Chen, S. Z., Low, P. F. and Roth, C. B., 1987 Relation between potassium fixation and the oxidation state of octahedral iron Soil Sci. Soc. Amer. J. 41 82 – 86.CrossRefGoogle Scholar
Eberhart, J. P., 1976 Méthodes Physiques d’Etude des Mineraux et des Materiaux Solides Paris Doen.Google Scholar
Goodman, B. A., Russell, J. D., Fraser, A. R. and Woodhams, F. W. D., 1976 A Mössbauer and I.R. spectroscopic study of the structure of nontronite Clays & Clay Minerals 24 53 – 59.CrossRefGoogle Scholar
Khaled, E. M. and Stucki, J. W. (1991) Effects of iron oxidation state on cation fixation in smectites: Soil Sci. Soc. Amer. J. 55, (in press).CrossRefGoogle Scholar
Komade, I.P. Lear, P.R. and Stucki, J.W., 1990 Reduction and reoxidation of iron in nontronites: Rate of reaction and extent of reduction Clays & Clay Minerals 37 203 – 208.CrossRefGoogle Scholar
Lear, P. R. and Stucki, J. W., 1985 Role of structural hydrogen in the reduction and reoxidation of iron in nontronite Clays & Clay Minerals 33 539 – 545.CrossRefGoogle Scholar
Lear, P. R. and Stucki, J. W., 1987 Intervalence electron transfer and magnetic exchange in reduced nontronite Clays & Clay Minerals 35 373 – 378.CrossRefGoogle Scholar
Lear, P. R. and Stucki, J. W., 1989 Effects of iron oxidation state on the specific surface area of nontronite Clays & Clay Minerals 37 547 – 552.CrossRefGoogle Scholar
Méring, J., Oberlin, A. and Bailey, S. W., 1967 Electron-optical study of smectites Clays and Clay Minerals, Proc. 15th Natl. Conf., Pittsburgh, Pennsylvania, 1966 New York Pergamon Press 3 – 25.Google Scholar
Murad, E., 1987 Mössbauer spectra of nontronites: Structural implications and characterization of associated iron oxides Z. Pflanzernähr. Bodenk. 150 279 – 285.CrossRefGoogle Scholar
Russell, J. D. and Clark, D. R., 1978 The effect of Fe-for-Si substitution on the b-dimension of nontronite Clay Miner. 13 133 – 138.CrossRefGoogle Scholar
Stucki, J. W., Stucki, J. W., Goodman, B. A. and Schwertmann, U., 1988 Structural iron in smectites Iron in Soils and Clay Minerals The Netherlands D. Reidel, Dordrecht 625 – 675.CrossRefGoogle Scholar
Stucki, J. W., Golden, D. C. and Roth, C. B., 1984 The preparation and handling of dithionite-reduced smectite suspensions Clays & Clay Minerals 32 191 – 197.CrossRefGoogle Scholar
Stucki, J. W., Low, P. F., Roth, C. B. and Golden, D. C., 1984 Effects of oxidation state of octahedral iron on clay swelling Clays & Clay Minerals 32 357 – 362.CrossRefGoogle Scholar
Stucki, J. W., Lear, P. R., Coyne, L. M., Blake, D. and McKeever, S., 1989 Variable oxidation states of iron in the crystal structure of smectite clay minerals Structures and Active Sites of Minerals Washington, D.C. American Chemical Society 330 – 358.Google Scholar
Suquet, H. and Pezerat, H., 1987 Parameters influencing layer stacking types in saponite and vermiculite: A review Clays & Clay Minerals 35 353 – 362.CrossRefGoogle Scholar
Tessier, D., 1984 Etude experimentale de l’organisation des materiaux argileux: Hydratation, gonflement et structuration au cours de la dessiccation et de la réhumectation .Google Scholar
Tessier, D., Pédro, G., Schulze, L. G., van Olphen, H. and Mumpton, F. A., 1987 Mineralogical characterization of 2:1 clays in soils: Importance of the clay texture Proc. Int. Clay Conf., Denver, 1985 Bloomington, Indiana The Clay Minerals Society 78 – 84.Google Scholar
van Olphen, H., 1963 An Introduction to Clay Colloid Chemistry New York Wiley 251 – 270.Google Scholar
Wu, J., Low, P. F. and Roth, C. B., 1989 Effects of octahedral-iron reduction and swelling pressure on interlayer distances in Na-nontronite Clays & Clay Minerals 37 211 – 218.Google Scholar