Asymmetrical ammonium-based gemini ionic liquids, 1-trimethylammonium-3-(1-methylpiperidinium)propane dibis[(trifluoromethyl)sulfonyl]imide ([N 111 C 3 MPip][NTf 2 ] 2 ) and 1-trimethylammonium-3-(4-methylmorpholinium)propane dibis[(trifluoromethyl)sulfonyl]imide ([N 111 C 3 MMor][NTf 2 ] 2 ), were synthesized and structurally characterized by 1 H NMR, 13 C NMR, and MS. The melting temperatures and associated enthalpies and entropies of fusion of these gemini ionic liquids have been determined through differential scanning calorimetry (DSC). Thermal stabilities of [N 111 C 3 MPip][NTf 2 ] 2 and [N 111 C 3 MMor][NTf 2 ] 2 have been investigated by thermogravimetric analysis technology under pure nitrogen atmosphere. The solubility data of [N 111 C 3 MPip][NTf 2 ] 2 and [N 111 C 3 MMor][NTf 2 ] 2 in water, ethanol, benzyl alcohol, 2-phenylethanol and n -heptane were determined by a synthetic method using a laser monitoring observation technique in the temperature range 298.15–333.15 K under atmospheric pressure. The solubility in all pure solvents increased with the increasing temperature and the greatest solubilities of both gemini ionic liquids were observed in benzyl alcohol. The modified Apelblat, Buchowski–Ksiazaczak λh and NRTL models were employed to correlate the experimental solubility data. The calculated results show good agreement with the experimental data and modified Apelblat and λh equations are more accurate than the NRTL model. The standard state enthalpy, entropy, and Gibbs energy of dissolution of the GILs in the studied solvents were evaluated through the van′t Hoff equation using the experimental solubility data. The excess enthalpies of the solutions were also determined by the λh model. The dissolution behavior can serve for the synthesis and purification process of GILs.

中文翻译：

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铵基双子离子液体在纯溶剂中的溶解度和热力学性质

不对称铵基双子离子液体，1-三甲基铵-3-(1-甲基哌啶鎓)丙烷二双[(三氟甲基)磺酰基]亚胺([N 111 C 3 MPip][NTf 2 ] 2 )和1-三甲基铵-3-(合成了 4-甲基吗啉鎓）丙烷二双[（三氟甲基）磺酰基]亚胺（[N 111 C 3 MMor][NTf 2 ] 2 ），并通过 1 H NMR、 13 C NMR 和 MS 对其进行了结构表征。这些双子离子液体的熔化温度和相关的熔化焓和熵已通过差示扫描量热法 (DSC) 确定。[N 111 C 3 MPip][NTf 2 ] 2 和[N 111 C 3 MMor][NTf 2 ] 2 的热稳定性已通过热重分析技术在纯氮气氛下进行了研究。[N 111 C 3 MPip][NTf 2 ] 2 和[N 111 C 3 MMor][NTf 2 ] 2 在水、乙醇、苯甲醇中的溶解度数据，2-苯基乙醇和正庚烷通过合成方法使用激光监测观察技术在298.15-333.15 K的温度范围内在大气压下测定。在所有纯溶剂中的溶解度随着温度的升高而增加，并且在苯甲醇中观察到两种双子离子液体的最大溶解度。采用改进的 Apelblat、Buchowski-Ksiazaczak λh 和 NRTL 模型来关联实验溶解度数据。计算结果与实验数据吻合良好，修改后的 Apelblat 和 λh 方程比 NRTL 模型更准确。使用实验溶解度数据，通过 van't Hoff 方程评估 GIL 在所研究溶剂中的标准态焓、熵和吉布斯溶解能。溶液的过量焓也由 λh 模型确定。溶解行为可用于 GILs 的合成和纯化过程。