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常压KCl溶液中α-半水石膏的脱水过程

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Abstract:

一般认为,在盐溶液中,亚稳态的α-半水石膏(α-Hemi-hydratedgypsum,α-HH)脱水转变为无水石膏(calciumsulfateanhydrite,AH)是直接脱水的过程。研究常压、80~102℃条件下KCl溶液中α-HH的脱水行为,通过热分析和物相测定阐明α-HH的脱水过程和产物。结果表明KCl溶液中α-HH的脱水过程有2个相转化途径一个是α-半水石膏→二水石膏(calciumsulfatedihydrate,DH)→无水石膏(α-HH→DH→AH)历程;另一个是α-半水石膏→无水石膏(α-HH→AH)历程。α-HH脱水转化为无水石膏的过程伴随有钾石膏的生成。α-HH在KCl溶液中的脱水速率和脱水途径取决于KCl浓度和反应温度。

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