Thermal investigations on alunite and its mixtures with quartz and dickite
- 1 March 1969
- journal article
- Published by Mineralogical Society in Mineralogical Magazine
- Vol. 37 (285), 128-134
- https://doi.org/10.1180/minmag.1969.037.285.13
Abstract
Summary: The thermal decomposition of alunite and of mixtures of alunite with dickite or quartz or both has been studied, and X-ray determinations of the products at various stages of the decomposition have been made. Between 600 and 700°C the product from alunite is a mixture of anhydrous alum and amorphous alumina; between 700 and 770°C the anhydrous alum breaks down into aluminium sulphate and alkali sulphate; then in the prominent 850°C endothermic reaction three-quarters of the sulphate is lost, leaving a mixture of alkali sulphate and γ-alumina. The area of the 850 °C endothermic peak may be used as a measure of the percentage of alunite in alunitized rocks (alunite-quartz-dickite mixtures).Keywords
This publication has 4 references indexed in Scilit:
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