Hostname: page-component-848d4c4894-ttngx Total loading time: 0 Render date: 2024-06-04T12:34:05.125Z Has data issue: false hasContentIssue false

Preparation and Characterization of Reduced-Charge Hectorites

Published online by Cambridge University Press:  28 February 2024

William F. Jaynes
Affiliation:
Agronomy Department, The Ohio State University, Columbus, Ohio 43210
Samuel J. Traina
Affiliation:
Agronomy Department, The Ohio State University, Columbus, Ohio 43210
Jerry M. Bigham
Affiliation:
Agronomy Department, The Ohio State University, Columbus, Ohio 43210
Cliff T. Johnston
Affiliation:
Department of Soil Science, University of Florida, Gainesville, Florida 32611

Abstract

A series of reduced-charge (RC) hectorites were prepared by multiple heat (250°C) treatments of Mg-saturated hectorites (SHCa-1 ). Cation exchange capacity (CEC) measurements and alkylammonium exchange indicated that a decrease in layer charge occurred with each Mg-250 treatment. Chemical analyses showed that decreases in structural Li and increases in structural Mg contents coincided with charge reduction. Fluorescence measurements of adsorbed quinoline indicated that the hectorite surface was acidified during charge reduction; hydroxyl group deprotonation is a possible source for the acidity. Fourier transform infrared spectra (FTIR) indicated that the Mg-250 treatment induced the loss of structural Li and shifted the SiO stretch band to a position similar to that in talc. The relative intensities of the OH and SiO stretch bands in FTIR spectra suggest that some of the hydroxyl groups in hectorite were lost, possibly by deprotonation. However, thermogravimetric data (TG) reveal no significant difference in the hydroxyl contents of the hectorites.

The FTIR spectra, CEC, layer charge, chemical, and TG data all supported the view that Mg substitution for octahedral Li occurred which resulted in a more “talc-like” structure. Charge reduction in smectites is evidently a general phenomenon and can be induced by heat treatment with the proper exchangeable cation. The ability to reduce the charge of hectorites makes it possible to prepare a series of clays which vary in charge but lack structural Fe. Such RC smectites should be suitable for expandable clay mineral studies which utilize spectroscopic techniques that are sensitive to Fe content.

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Ainsworth, C. C., Zachara, J. M. and Schmidt, R. L., 1987 Quinoline sorption on Na-montmorillonite: Contributions of the protonated and neutral species Clays & Clay Minerals 35 121128 10.1346/CCMN.1987.0350204.CrossRefGoogle Scholar
Bernas, B., 1968 A new method for decomposition and comprehensive analysis of silicates by atomic absorption spectrometry Anal. Chem 40 16821686 10.1021/ac60267a017.CrossRefGoogle Scholar
Brindley, G. W. and Ertem, G., 1971 Preparation and solvation properties of some variable charge montmorillonites Clays & Clay Minerals 19 399404 10.1346/CCMN.1971.0190608.CrossRefGoogle Scholar
Brindley, G. W., LeMaitre, J. and Newman, A. C. D., 1987 Thermal, oxidation and reduction reactions of clay minerals Chemistry of Clays and Clay Minerals 319370.Google Scholar
Byström-Brusewitz, A. M. and Bailey, S. W., 1976 Studies of the Li test to distinguish beidellite and montmorillonite Proc. Int. Clay Conf, Mexico City, 1975 Wilmette, Illinois Applied Publishing 419428.Google Scholar
Calvet, R. and Prost, R., 1971 Cation migration into empty octahedral sites and surface properties of clays Clays & Clay Minerals 19 175186 10.1346/CCMN.1971.0190306.CrossRefGoogle Scholar
Chen, Y., Shaked, D. and Banin, A., 1979 The role of structural iron(III) in the UV absorption by smectites Clay Miner 14 93102 10.1180/claymin.1979.014.2.01.CrossRefGoogle Scholar
Farmer, V. C., 1974 The infrared spectra of minerals Mineralogical Society Monograph 4 London Mineralogical Society 331363.Google Scholar
Farmer, V. C., van Olphen, H. and Fripiat, J. J., 1979 Infrared spectroscopy Data Handbook for Clay Materials and Other Non-metallic Minerals Oxford Pergamon Press 285337.Google Scholar
Farmer, V. C. and Russell, J. D., 1967 Infrared absorption spectrometry in clay studies Clays & Clay Minerals 15 121142 10.1346/CCMN.1967.0150112.CrossRefGoogle Scholar
Hofmann, U. and Kiemen, R., 1950 Verlust der Austauschfähigkeit von Lithiumionen an Bentonit durch Erhitzung Z. Anorg. Allg. Chem 262 9599 10.1002/zaac.19502620114.CrossRefGoogle Scholar
Jaynes, W. F. and Bigham, J. M., 1986 Multiple cationexchange capacity measurements on standard clays using a commercial mechanical extractor Clays & Clay Minerals 34 9398 10.1346/CCMN.1986.0340112.CrossRefGoogle Scholar
Jaynes, W. F. and Bigham, J. M., 1987 Charge reduction, octahedral charge, and lithium retention in heated, Li-saturated smectites Clays & Clay Minerals 35 440448 10.1346/CCMN.1987.0350604.CrossRefGoogle Scholar
Karickhoff, S. W. and Bailey, G. W., 1976 Protonation of organic bases in clay-water systems Clays & Clay Minerals 24 170176 10.1346/CCMN.1976.0240404.CrossRefGoogle Scholar
Lim, C. H. and Jackson, M. L., 1986 Expandable phyllosilicate reactions with lithium on heating Clay & Clay Minerals 34 346352 10.1346/CCMN.1986.0340316.CrossRefGoogle Scholar
Mackenzie, R. C., Caillère, S., van Olphen, H. and Fripiat, J. J., 1979 Thermal analysis, DTA, TG, DTG Data Handbook for Clay Materials and Other Non-metallic Minerals Oxford Pergamon Press 243284.Google Scholar
Rühlicke, G. and Kohler, E. E., 1981 A simplified procedure for determining layer charge by the n-alkylammonium method Clay Miner 16 305307 10.1180/claymin.1981.016.3.08.CrossRefGoogle Scholar
Rupert, J. P., Granquist, W. T., Pinnavaia, T. J. and Newman, A. C. D., 1987 Catalytic properties of clay minerals Chemistry of Clay Minerals Longman Scientific & Technical Mineralogical Society 275318.Google Scholar
Shapiro, L. and Brannock, W. W., 1962 Rapid Analysis of Silicate, Carbonate, and Phosphate Rocks .Google Scholar
Sposito, G., Prost, R. and Gaultier, J. P., 1983 Infrared spectroscopic study of adsorbed water on reduced-charge Na/Li-montmorillonites Clays & Clay Minerals 31 916 10.1346/CCMN.1983.0310102.CrossRefGoogle Scholar
Traina, S. J., 1990 Applications of luminescence spectroscopy to studies of colloid-solution interfaces Advan. Soil Sci 14 167190 10.1007/978-1-4612-3356-5_5.CrossRefGoogle Scholar
van der Marel, H. W. and Beutelspacher, H., 1976 Atlas of Infrared Spectroscopy of Clay Minerals and Their Admixtures New York Elsevier Scientific.Google Scholar