Study of gypsum by PDSC
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Calcium sulfate dihydrate has been widely characterized by both differential scanning calorimetry and thermogravimetry (TG). Two dehydration processes were reported to be partially overlapping. High resolution TG and water vapor self generated atmosphere pin-hole lid strategies were used to increase the resolution of both dehydration processes. In this study, isobaric experiments were carried out in a pressure differential scanning calorimetry cell. The approach consisted in combining the pin-hole lid with different pressures with nitrogen atmosphere. Resolution was improved at moderately low pressures. At higher pressures other processes were observed.
KeywordsGypsum PDSC Pressure Crystallization Vapor Water
This study was partially funded by the Spanish Ministerio de Educacion y Ciencia MTM2008-00166 and MAT2010-21342-C02-01.
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