Mulero Ángel, Hernández Ariel, Vadillo-Rodríguez Virginia, Cachadiña Isidro
Departamento de Física Aplicada, Universidad de Extremadura, Spain.
Facultad de Ingeniería y Negocios, Universidad de Las Américas, Concepción, Chile.
Phys Chem Chem Phys. 2025 Jun 18;27(24):12812-12836. doi: 10.1039/d5cp01354b.
In this work, a large data set of experimental values of surface tension for binary mixtures of two -alkanes have been compiled. These values are later fitted to different models of correlation as functions of molar fraction at various temperatures. All of these models use the surface tension of pure fluids as input data and may require between one and three adjustable coefficients. For some mixtures and/or temperatures, where the surface tension values of pure fluids have not been measured, predictions from previously proposed specific correlations for pure fluids are considered as an alternative. Different cases are studied accordingly with the availability of surface tension values for pure fluids: (i) available for both pure fluids, (ii) available for only one of the fluids, and (iii) unavailable for both fluids. Moreover, a fourth case is considered to include those mixtures and temperatures at which one of the fluids is supercritical. The applicability and accuracy of 10 different analytical correlation models are evaluated based on the percentage deviations between experimental and calculated values. Additionally, the Akaike information criterion is applied to identify the most suitable models. As a main result, it is found that predicted values from correlations for pure fluids can be used instead of experimental data without significantly affecting the accuracy and applicability of the models. Moreover, it is shown that the Winterfeld-Scriven-Davis model, which has a certain physicochemical basis and only one adjustable coefficient, provides the best overall results. However, this model cannot be applied when one of the fluids is supercritical and its surface tension is assumed to be zero. In this case, the Redlich-Kister correlation, with two or three adjustable coefficients, provides better results. More recent or more complex models are not necessary to achieve excellent accuracy for -alkane mixtures and therefore should be avoided.
在这项工作中，已汇编了一个包含两种烷烃二元混合物表面张力实验值的大型数据集。这些值随后被拟合到不同的关联模型中，作为不同温度下摩尔分数的函数。所有这些模型都将纯流体的表面张力用作输入数据，并且可能需要一到三个可调系数。对于某些混合物和/或温度，若尚未测量纯流体的表面张力值，则可考虑使用先前提出的针对纯流体的特定关联式进行预测。根据纯流体表面张力值的可得情况，相应地研究了不同情形：(i) 两种纯流体的值均可得；(ii) 仅有一种流体的值可得；(iii) 两种流体的值均不可得。此外，还考虑了第四种情形，即包括其中一种流体处于超临界状态的那些混合物和温度。基于实验值与计算值之间的百分比偏差，评估了10种不同解析关联模型的适用性和准确性。此外，应用赤池信息准则来识别最合适的模型。主要结果表明，纯流体关联式的预测值可替代实验数据，而不会显著影响模型的准确性和适用性。此外，结果表明具有一定物理化学基础且仅有一个可调系数的温特费尔德 - 斯克里文 - 戴维斯模型提供了最佳的总体结果。然而，当其中一种流体处于超临界状态且其表面张力被假定为零时，该模型无法应用。在这种情况下，具有两个或三个可调系数的雷德利希 - 基斯特关联式能提供更好的结果。对于烷烃混合物而言，不需要更新的或更复杂的模型就能实现优异的准确性，因此应避免使用这类模型。
