Institut für Chemie, Abteilung für Physikalische Chemie, Universität Rostock, 18059 Rostock, Germany.
Department Life, Light & Matter, University of Rostock, 18059 Rostock, Germany.
Molecules. 2022 Apr 3;27(7):2321. doi: 10.3390/molecules27072321.
Ionic liquids (ILs) are recognized as an environmentally friendly alternative to replacing volatile molecular solvents. Knowledge of vaporization thermodynamics is crucial for practical applications. The vaporization thermodynamics of five ionic liquids containing a pyridinium cation and the [NTf] anion were studied using a quartz crystal microbalance. Vapor pressure-temperature dependences were used to derive the enthalpies of vaporization of these ionic liquids. Vaporization enthalpies of the pyridinium-based ionic liquids available in the literature were collected and uniformly adjusted to the reference temperature = 298.15 K. The consistent sets of evaluated vaporization enthalpies were used to develop the "centerpiece"-based group-additivity method for predicting enthalpies of vaporization of ionic compounds. The general transferability of the contributions to the enthalpy of vaporization from the molecular liquids to the ionic liquids was established. A small, but not negligible correction term was supposed to reconcile the estimated results with the experiment. The corrected "centerpiece" approach was recommended to predict the vaporization enthalpies of ILs.
离子液体 (ILs) 被认为是替代挥发性分子溶剂的环保替代品。了解蒸发热力学对于实际应用至关重要。使用石英晶体微天平研究了含有吡啶阳离子和 [NTf] 阴离子的五种离子液体的蒸发热力学。通过蒸汽压-温度关系得出了这些离子液体的蒸发焓。收集了文献中可用的基于吡啶的离子液体的蒸发焓，并将其统一调整到参考温度 = 298.15 K。使用一致的评估蒸发焓集开发了基于“中心件”的基团加和法来预测离子化合物的蒸发焓。从分子液体到离子液体的蒸发焓的贡献具有普遍的可转移性。假设一个小但不可忽略的校正项来使估算结果与实验结果相符。推荐使用校正后的“中心件”方法来预测 ILs 的蒸发焓。
