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Some applications of thermohygrometric analysis to the study of clay and associated minerals

Published online by Cambridge University Press:  09 July 2018

M. H. Creer
Affiliation:
The General Electric Company Limited, Central Research Laboratories, Hirst Research Centre, Wembley
J. B. C. Hardy
Affiliation:
The General Electric Company Limited, Central Research Laboratories, Hirst Research Centre, Wembley
H. P. Rooksby
Affiliation:
The General Electric Company Limited, Central Research Laboratories, Hirst Research Centre, Wembley
J. E. Still
Affiliation:
The General Electric Company Limited, Central Research Laboratories, Hirst Research Centre, Wembley

Abstract

A new method of measuring the water evolved on thermal dehydration of a variety of clay minerals and related hydrated compounds is described. By placing the substance in a tubular furnace and passing over it a dry inert gas, water released on heating is carried to a sensitive electrolytic hygrometer for measurement. The heating is programmed to give a uniform rate of temperature rise, so that continuous monitoring of the evolved water permits discrimination between successive dehydration processes occurring at different temperatures. The procedure is appropriately termed thermohygrometric analysis (THA).

The applications described include investigations of the thermal decomposition behaviours of hydrated aluminas and hydrated iron oxides, and of clay minerals such as kaolin, montmorillonite, chrysotile and micas. The relations between the results given by thermohygrometric analysis and those obtained by differential thermal analysis are discussed. As with DTA, the record trace from a THA examination gives a graphical representation of the dehydration process, but THA has an advantage in providing a quantitative measurement of the water evolved.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1971

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References

Bain, J.A. & Morgan, D.J. (1969) Clay Miner. 8, 171.CrossRefGoogle Scholar
Keidel, H.A. (1959) Analyt. Chem. 31, 2043.Google Scholar
Kubisz, J. & Stoch, L. (1965) Proc. 1st Inter. Conf. Thermal Analysis (ed. J. P. Redfern), Macmillan, London.Google Scholar
Kulbicki, G. & Grim, R.E. (1959) Mineralog. Mag. 32, 53.Google Scholar
Oosterhout, G.W. Van (1964) Proc. Inter. Conf. Magnetism, p. 529, Institute of Physics, London.Google Scholar
Rooksby, H.P. (1961) The X-ray Identification and Crystal Structures of Clay Minerals (G. Brown, editor), p. 363. Mineralogical Society, London.Google Scholar
Still, J.E. & Chirnside, R.C. (1968) Nature, 219, 200.Google Scholar
Still, J.E. & Cluley, H.J. (1965) Proc. Soc. anal. Chem. Conference, Nottingham, p. 405.Google Scholar