Hostname: page-component-8448b6f56d-c4f8m Total loading time: 0 Render date: 2024-04-23T17:46:18.070Z Has data issue: false hasContentIssue false
  • English
  • Français

Effect of Ambient Atmosphere on Solid State Reaction of Kaolin-Salt Mixtures

Published online by Cambridge University Press:  02 April 2024

M. Gábor ,
L. Pöppl  and
E. Körös
M. Gábor
Affiliation:
Institute of Inorganic & Analytical Chemistry, L. Eötvös University, P.O. Box 123, H-1443 Budapest, Hungary
L. Pöppl
Affiliation:
Institute of Inorganic & Analytical Chemistry, L. Eötvös University, P.O. Box 123, H-1443 Budapest, Hungary
E. Körös
Affiliation:
Institute of Inorganic & Analytical Chemistry, L. Eötvös University, P.O. Box 123, H-1443 Budapest, Hungary
Get access Rights & Permissions [Opens in a new window]

Abstract

The reaction of kaolin with NaCl was followed by dynamic thermal analysis and mass spectrometry under N2, CO2, and air atmospheres and in a 10−5-torr vacuum. The weight loss was a function of the atmosphere used and, according to mass spectrometry, was due to the evolution of H2O, HCl, and very small amounts of H2. HCl was formed only after the release of 85% of the hydroxyl content of the kaolin. When the clay was pretreated with saturated salt solution, H2O and HCl evolved in more or less the same temperature range, indicating that only some of the OH groups reacted with the chloride ion. High-temperature X-ray powder diffraction patterns showed that the sodium ion reacted with the noncrystalline metakaolin to give NaAlSiO4. Chemical analysis showed that the reaction of kaolinite and sodium chloride started below 400°C. The rate of the reaction increased at higher water vapor concentration. From mass spectrometric data, the NaCl-treated kaolin appeared to adsorb CO2. Desorption at several distinct temperatures suggests that CO2 was adsorbed by different parts of the structure, i.e., holes and channels. X-ray powder diffraction and infrared absorption data indicate that the kaolinite structure persisted even after it had been heated with NaCl in a CO2 atmosphere to as high as 800°C.

Keywords

Infrared spectroscopyGaseous atmosphereKaolinMetakaolinSaltThermal analysis
Type
Research Article
Information
Clays and Clay Minerals , Volume 34 , Issue 5 , October 1986 , pp. 529 - 533
Copyright
Copyright © 1986, 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

Claws, F. H., 1922 Interaction of sodium chloride and silicon J. Chem. Soc. 121 1442–1444.CrossRefGoogle Scholar
Fanner, C. V., 1966 Dehydration reactions in alkali halide pressed disks Spectrochim. Acta 22 1053–1056.Google Scholar
Freund, F., Wengeler, H., Kathrein, H., Knobel, R., Oberheuser, G. C., Maiti, G., Reil, D., Rnipping, U. and Kötz, J., 1983 Hydrogen and carbon derived from dissolved H2O and CO2 in minerals Bull. Mineral. 106 185–200.Google Scholar
Gâbor, M., Wajand, J., Pöppl, L., Szabô, Z. G. and Wood, J., 1977 Steps in low temperature dehydroxylation of clay Reactivity of Solids New York Plenum Press 761–765.CrossRefGoogle Scholar
Hedwall, A. J., 1966 Solid State Chemistry New York Elsevier.Google Scholar
Heller-Kallai, L., 1975 Montmorillonite-alkali halide interaction—a possible mechanism for illitization Clays & Clay Minerals 23 462–467.CrossRefGoogle Scholar
Heller-Kallai, L., 1978 Reactions of salts with kaolinite at elevated temperatures. I Clay Miner. 13 221–235.CrossRefGoogle Scholar
Jagitsch, R., 1958 Reaction between anhydrous sodium carbonate and metakaolin Z. Naturforsch. A. 13 97–101.Google Scholar
Mackenzie, K. J. D., 1968 The effects of impurities on the formation of mullite from kaolinite-type minerals: III. The effect of the firing atmosphere J. Amer. Ceram. Soc. 51 103–109.Google Scholar
Martens, R., Gentsch, H. and Freund, F., 1976 Hydrogen release during the thermal decomposition of magnesium hydroxide to magnesium J. Catal. 44 366–372.CrossRefGoogle Scholar
Nägerl, H. and Freund, F., 1970 Zersetzungsmechanismus von Mg(OH)2 und Mg(OD)2 J. Thermal Anal. 2 387–395.CrossRefGoogle Scholar
Sandford, F., 1951 Effect of composition of kiln atmosphere in the firing of refractory oxides J. Amer. Ceram. Soc. 34 179–183.CrossRefGoogle Scholar
Wada, K., 1961 Lattice expansion of kaoline minerals by treatment with potassium acetate Amer. Mineral. 46 78–91.Google Scholar
Wilson, M. C. and Galwey, A. K., 1975 Compensation effect in heterogenous catalytic reactions including hydrocarbon formation on clays Nature 243 402–404.CrossRefGoogle Scholar
Yariv, S., 1975 Effects of grinding of kaolinite with potassium bromide Clays & Clay Minerals 23 80–82.CrossRefGoogle Scholar