Abstract

The solubilities of salts in the MgSO₄–H₂O and CdSO₄–H₂O systems are studied at 276–500°C using various methods (visual examination of phase transformations in water–salt mixtures in sealed quartz ampoules, collecting solution samples and performing chemical analysis, and measuring p–V–T dependences in an autoclave) to determine temperature dependence and classify the compounds as one the of two types (type 1 or type 2) according to the classification of inorganic salts. In the studied temperature range, the solubility of these salts is very low at pressures below 157 MPa and decreases when approaching the critical point of water. The systems under study are found to be classified as type 2 water–salt systems having the critical point (G = L – S) lying near the critical point of water. No separation of fluid into two liquid phases was detected at temperatures below 500°C and pressures below 157 MPa, thus indicating that the second critical point (L₁ = L₂ – S) has very high parameters. The resulting data can be used for elaborating methods for raw material processing.

中文翻译：

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高温高压下硫酸镁和镉镉在水中的溶解度

摘要

使用各种方法在276–500°C下研究了MgSO ₄ –H ₂ O和CdSO ₄ –H ₂ O系统中盐的溶解度（目视检查密封石英安瓿中水盐混合物的相变，收集溶液样品并进行化学分析，并测量p–V–T确定是否具有温度依赖性，并根据无机盐的分类将化合物分类为两种类型（类型1或类型2）之一。在研究的温度范围内，这些盐的溶解度在低于157 MPa的压力下非常低，并且在接近水的临界点时会降低。发现所研究的系统被归类为2类水盐系统，其临界点（G = L – S）位于水的临界点附近。在低于500°C的温度和低于157 MPa的压力下，未检测到流体分为两个液相，因此表明第二个临界点（L ₁ = L ₂ – S）具有很高的参数。所得数据可用于详细说明原材料处理的方法。