Estimation of the diffusion coefficient of water evolved during the non-isothermal dehydration of Australian sedimentary opal

Publication Type:
Journal Article
Journal of Thermal Analysis and Calorimetry, 2007, 88 (1), pp. 231 - 235
Issue Date:
Filename Description Size
Thumbnail2006011458.pdf304.92 kB
Adobe PDF
Full metadata record
The dehydration of an opal specimen was investigated by thermogravimetric analysis (TG) in powder and bulk forms. The change in geometry resulted in a significant difference in the temperature range in which dehydration occurred with peak temperatures in the differential TG (DTG) curve for the hand ground opal at 203°C and for the bulk opal at 340°C. This difference was attributed to time taken for diffusion of free water in the bulk opal to the specimen surface prior to evolution as a registered mass loss. A model was proposed to account for the diffusion of water and was used to estimate the diffusion coefficient. © Springer-Verlag 2007.
Please use this identifier to cite or link to this item: