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Site Occupancy in Nontronite Studied by Acid Dissolution and Mössbauer Spectroscopy

Published online by Cambridge University Press:  28 February 2024

Vittorio Luca*
Affiliation:
Chemistry Department, Victoria University of Wellington, P.O. Box 600, Wellington, New Zealand
Dugald J. MacLachlan*
Affiliation:
Chemistry Department, Victoria University of Wellington, P.O. Box 600, Wellington, New Zealand
*
1Present address: Research School of Chemistry, The Australian National University, Canberra, ACT 2601, Australia
2Present address: Department of Biology, University College, London WC1E6BT, England.
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Abstract

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The dissolution of two Ca2+-exchanged nontronite samples has been studied in 10% HCl. Early acid-dissolution studies (Osthaus, 1954) have indicated that after two hours of dissolution most of the octahedral Fe3+ (VIFe3+) would be removed leaving mainly tetrahedral Fe3+ (IVFe3+) in the nontronite structure. In the present study, 57Fe Mössbauer spectra of acid-treated samples were recorded and fitted with two octahedral Fe3+ (2 × VIFe3+) and two octahedral and one tetrahedral (2 × VIFe3+, 1 × IVFe3+) doublet models. The Mössbauer spectra of acid-treated Garfield nontronite samples could be adequately fitted with two-doublet models but acid-treated Hohen Hagen nontronite samples could not. Isomer shift and quadrupole splitting values obtained from the two-doublet models corresponded to VIFe3+ and not IVFe3+, as was suggested by the Osthaus (1954) experiment. When an IVFe3+ doublet was included in the model used to fit the Mössbauer spectra of acid-treated Garfield nontronite samples, a slight increase in the intensity of the IVFe3+ doublet occurred with increasing dissolution, but this was much lower than indicated by Osthaus (1954). No trend in the intensity of the IVFe3+ doublet was observed for acid-treated Hohen Hagen nontronite. Therefore, acid treatment appears to remove VIFe3+ and IVFe3+ from the nontronite structure at about the same rate. Mössbauer spectroscopy, infrared spectroscopy and X-ray powder diffraction data indicate that the nontronite that remains undissolved following acid treatment is structurally similar to the untreated nontronite.

Type
Research Article
Copyright
Copyright © 1992, The Clay Minerals Society

References

Besson, G., Bookin, A. S., Dainyak, L. G., Rautureau, M., Tsipursky, S. L., Tchoubar, G. and Drits, V. A., 1983 Use of diffraction and Mössbauer methods for the structural and crystallochemical characterization of nontronites J. Appl. Cryst 16 374383 10.1107/S0021889883010651.CrossRefGoogle Scholar
Bonnin, D., Calas, G., Suquet, H. and Pezerat, H., 1985 Site occupancy in Garfield nontronite: A spectroscopic study Phys. Chem. Miner 12 5564.CrossRefGoogle Scholar
Brindley, G. W. and Youell, R. F., 1951 A chemical determination of tetrahedral aluminum ions in a silicate Acta Crystallogr 4 495496 10.1107/S0365110X51001689.CrossRefGoogle Scholar
Cabrera, F. and Talibudeen, O., 1978 The release of aluminum from aluminosilicate minerals. I. Kinetics Clays & Clay Minerals 26 434440 10.1346/CCMN.1978.0260607.CrossRefGoogle Scholar
Cardile, C. M., 1988 Tetrahedral iron in smectites: A critical comment Clays & Clay Minerals 37 185189 10.1346/CCMN.1989.0370211.CrossRefGoogle Scholar
Gastuche, M. C. and Fripiat, J. J., 1962 Acid solution techniques applied to the structures of clay and controlled by physical methods Sci. Ceram 1 121138.Google Scholar
Glaeser, R., Mering, J. and Bailey, S. W., 1975 Influence du taux de substitution isomorphique en couche tetraédrique sur les propriétés et l’organisation structurale des smectites dioctaé-driques Proc. 5th Int. Clay Conf., Mexico City, 1975 Illinois Applied Publishing, Wilmette 173183.Google Scholar
Goodman, B. A., Russell, J. D. and Fraser, A. R., 1976 A Mössbauer and IR spectroscopic study of the structure of nontronite Clays & Clay Minerals 24 5459 10.1346/CCMN.1976.0240201.CrossRefGoogle Scholar
Grandstaff, D. E., 1977 Some kinetics of bronzite ortho-pyroxene dissolution Geochim. Cosmochim. Acta 41 10971103 10.1016/0016-7037(77)90104-1.CrossRefGoogle Scholar
Holdren, G. R. Jr. and Adams, J. E., 1982 Parabolic dissolution kinetics of silicate minerals: An artifact of non-equilibrium dissolution processes? Geology 10 186190 10.1130/0091-7613(1982)10<186:PDKOSM>2.0.CO;2.2.0.CO;2>CrossRefGoogle Scholar
Holdren, G. R. Jr. and Berner, R. A., 1979 Mechanism of feldspar weathering. I. Experimental studies Geochim. Cosmochim. Acta 43 11611171 10.1016/0016-7037(79)90109-1.CrossRefGoogle Scholar
Huang, W. H., Keller, W. D. and Serratosa, J. M., 1973 Kinetics and mechanisms of dissolution of Fithian illite in two complexing organic acids Proc. Int. Clay Conf., Madrid, 1972 Madrid, Spain Div. Ciencias C.S.I.C 321331.Google Scholar
Johnston, J. H. and Cardile, C. M., 1985 Iron sites in nontronite and the effect of interlayer cations from Möss-bauer spectra Clays & Clay Minerals 33 2130 10.1346/CCMN.1985.0330103.CrossRefGoogle Scholar
Karsulin, M. and Stubican, V., 1954 Über die Struktur und die Eigenschaften synthetischer Montmorillonite Monatsh. für Chemie 85 343358 10.1007/BF00904000.CrossRefGoogle Scholar
Law, A. D., 1973 Critical evaluation of statistical “best fits” to Mössbauer spectra Amer. Mineral 58 128131.Google Scholar
Luce, R. W., Bartlett, R. W. and Parks, G. A., 1972 Dissolution kinetics of magnesium silicates Geochim. Cosmochim. Acta 36 3550 10.1016/0016-7037(72)90119-6.CrossRefGoogle Scholar
Murphy, W. M. and Helgeson, H. C., 1987 Thermodynamic and kinetic constraints on reaction rates among minerals and aqueous solution. III. Activated complexes and the pH dependence of the rates of feldspar, pyroxene, wollastonite, and olivine hydrolysis Geochim. Cosmochim. Acta 51 31373153 10.1016/0016-7037(87)90124-4.CrossRefGoogle Scholar
Newman, A C D and Brown, G., 1969 Delayed exchange of potassium from some edges of mica flakes Nature 223 175176 10.1038/223175a0.CrossRefGoogle Scholar
Novak, I. and Cicel, B., 1978 Dissolution of smectites in hydrochloric acid: Rate as a function of crystallochemical composition Clays & Clay Minerals 26 341344 10.1346/CCMN.1978.0260504.CrossRefGoogle Scholar
Osthaus, B. B., 1954 Chemical determination of tetrahedral ions in nontronite Proc. 2nd Natl. Clay Conf, Columbia, Missouri, 1953 327 404416.Google Scholar
Poncelet, G., Schutz, A. and Setton, R., 1986 Pillared montmorillonite and beidellite. Acidity and catalytic properties Chemical Reactions in Organic and Inorganic Constrained Systems Dordrecht, Netherlands Reidel 165178 10.1007/978-94-009-4582-1_13.CrossRefGoogle Scholar
Ross, G. J., 1969 Acid dissolution of chlorites: Release of magnesium, iron, and aluminum and mode of acid attack Clays & Clay Minerals 17 347354 10.1346/CCMN.1969.0170604.CrossRefGoogle Scholar
Schneiderhöhn, P., 1965 Nontronit vom Hohen Hagen und Chloropal vom Meenser Steinberg bei Göttingen Tschermaks Min. Petr. Mitt 10 385399 10.1007/BF01128642.CrossRefGoogle Scholar
Schott, J., Berner, R. A. and Sjöberg, E. L., 1981 Mechanism of pyroxene and amphibole weathering. I. Experimental studies of iron-free minerals Geochim. Cosmochim. Acta 45 21232135 10.1016/0016-7037(81)90065-X.CrossRefGoogle Scholar
Sherman, D. M. and Vergo, N., 1988 Optical (diffuse reflectance) and Mössbauer spectroscopic study of nontronite and related Fe-bearing smectites Amer. Mineral 73 13461354.Google Scholar
Waychunas, G. A., 1986 Performance and use of Mössbauer goodness-of-fit parameters: Response to spectra of varying signal/noise ratio and possible misinterpretations Amer. Mineral 71 12611265.Google Scholar
Wieland, E., Wehrli, B. and Stumm, W., 1988 The coordination chemistry of weathering: III. A generalization on the dissolution rates of minerals Geochim. Cosmochim. Acta 52 19691981 10.1016/0016-7037(88)90178-0.CrossRefGoogle Scholar