Tool for the estimation of the melting enthalpy of PCM based on binary mixtures of salt + water.

Salt hydrates as phase change materials (PCM) are known for their high volumetric melting enthalpies and generally lower prices compared to organic PCM. However, obtaining a value for the melting enthalpy can prove to be difficult: while literature might not provide a(n) (accurate) value, determining the values experimentally can be time-consuming.
In the past, a theoretical model was developed to predict the melting entropies of salt hydrates. It is based on a linear relationship between the melting entropy of a salt hydrate and the number of moles of water of this salt hydrate. Here, this model is shown to be also valid in case of eutectic mixtures. Based on the model, a tool is defined which allows the estimation of the melting entropy and, hence, the melting enthalpy of a multitude of binary mixtures of salt + water.

水合盐作为相变材料（Phase Change Materials，PCM），以其较高的体积熔融焓以及相较于有机类相变材料更为低廉的价格而广为人知。然而，获取熔融焓的数值往往颇具挑战：即便现有文献未提供（准确的）数值，通过实验测定该参数也会耗费大量时间。此前已有研究开发出用于预测水合盐熔融熵的理论模型，该模型基于水合盐的熔融熵与其所含结晶水的物质的量之间的线性关系。本研究证明，该模型同样适用于共晶混合物体系。基于该模型，本研究构建了一款可用于估算大量盐-水二元混合物的熔融熵，进而推导其熔融焓的工具。