The thermodynamics of arsenates, selenites, and sulfates in the oxidation zone of sulfide ores: VIII. Field of thermal stability of synthetic analog of chalcomenite, its dehydration and dissociation
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The objective of this paper is to study the thermal stability of the synthetic analog of chalcomenite, CuSeO3 · 2H2O, and its dehydration and dissociation, in an experimental context. The study has been carried out by a comprehensive application of thermogravimetry (TG), differential scanning calorimetry (DSC), and high-temperature X-ray diffraction at a temperature range of 25–600°C. It has been established that CuSeO3 · 2H2O dehydrates at 202–264°C in three stages corresponding to the formation of intermediate CuSeO3 · 2H2O and CuSeO3 · 1/3H2O hydrate phases. At 480–595°C anhydrous CuSeO3 breaks down into CuO and SeO2 via the formation of a Cu4O(SeO3)3 phase. Enthalpies of the reactions at each stage of the CuSeO3 · 2H2O dehydration and CuSeO3 dissociation have been determined and their kinetic analysis has been carried out.
KeywordsDifferential Scanning Calorimetry Selenite Differential Scanning Calorimetry Curve Synthetic Analog Oxidation Zone
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