A Comparative Study of Thermal Effects on Surface and Structural Parameters of Natural Californian and Quebec Chrysotile Asbestos up to 700°C

William J. Murphy and Robert A. Ross
Department of Chemistry, Lakehead University, Thunder Bay, Ontario, Canada, P7B 5E1

Abstract: The effect of heat treatment on surface area, pore volume, pore size distribution, physical and chemical structure up to 700°C have been studied on samples of naturally occurring chrysotile minerals from California and Quebec. Techniques used included thermogravimetric analysis, low-temperature nitrogen adsorption, electron microscopy, X-ray powder and electron diffraction. The materials behaved similarly on heating to 100°C showing a 0.5% weight loss attributable to desorption of physisorbed water. At 500°C Quebec samples retained the chrysotile crystal structure while Californian samples were X-ray amorphous. Forsterite was formed by dehydration of both chrysotiles at 700°C; the greater stability of the Quebec samples to this process is explained by the presence of brucite as an impurity which enters into stray solid-solid interactions with the chrysotile.

Clays and Clay Minerals; May 1977 v. 25; no. 2; p. 78-89; DOI: 10.1346/CCMN.1977.0250202
© 1977, The Clay Minerals Society
Clay Minerals Society (www.clays.org)