Deep eutectic solvents (DESs) are newly introduced green solvents that have attracted much attention regarding fundamentals and applications. Of the problems along the way of replacing a common solvent by a DES, is the lack of information on the thermophysical properties of DESs. This is even more accentuated by considering the dramatically growing number of DESs, being made by the combination of vast numbers of the constituting substances, and at their various molar ratios. The speed of sound is among the properties that can be used to estimate other important thermodynamic properties. In this work, a global and accurate model is proposed and used to estimate the speed of sound in 39 different DESs. This is the first general speed of sound model for DESs. The model does not require any thermodynamic properties other than the critical properties of the DESs, which are themselves calculated by group contribution methods, and in doing so, make the proposed method entirely independent of any experimental data as input. The results indicated that the average absolute relative deviation percentages (AARD%) of this model for 420 experimental data is only 5.4%. Accordingly, based on the achieved results, the proposed model can be used to predict the speeds of sound of DESs.

中文翻译：

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估计深共晶溶剂中声速的全局模型

深共熔溶剂 (DES) 是新推出的绿色溶剂，在基本原理和应用方面引起了广泛关注。在用 DES 代替普通溶剂的过程中遇到的问题是缺乏有关 DES 热物理特性的信息。考虑到 DES 的数量急剧增加，这是由大量构成物质的组合及其各种摩尔比制成的，这一点更加突出。声速是可用于估计其他重要热力学属性的属性之一。在这项工作中，提出了一个全局且准确的模型，并用于估计 39 种不同 DES 中的声速。这是 DES 的第一个通用声速模型。除了 DES 的临界特性之外，该模型不需要任何热力学特性，这些特性本身是通过群贡献方法计算的，并且在这样做时，使所提出的方法完全独立于作为输入的任何实验数据。结果表明，该模型对420个实验数据的平均绝对相对偏差百分比（AARD%）仅为5.4%。因此，基于所取得的结果，所提出的模型可用于预测 DES 的声速。