Abstract Recently, deep eutectic solvents (DESs) have been introduced as new types of green solvents due to their environmentally friendly, non-toxicity, and favorable physicochemical properties over conventional organic solvents. Therefore, studying their physical properties will provide great help to design processes in the application fields. In this work, four new DESs are successfully prepared by using benzilic acid (BA) as hydrogen bond donor (HBD) with choline chloride (ChCl), tetraethylammonium bromide (TEAB), tetrapropylammonium bromide (TPAB), and tetrabutylammonium hydrogen sulfate (TBAHS) as hydrogen bond acceptors. The physicochemical properties of the DESs such as density, speed of sound, conductivity, viscosity, refractive index, and surface tension measured as a function of temperature. The melting temperatures of the DESs have been measured by using the Differential Scanning Calorimetry (DSC) method and the 1H, 13C NMR, and Fourier transforms infrared (FTIR) analysis carried out to confirm their chemical structure, purities, and occurrence interaction between the investigated HBAs and HBD which formed the deep eutectic mixtures.

中文翻译：

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新型苯甲酸基低共熔溶剂的制备和理化性质测定

摘要 近年来，深共熔溶剂（DESs）由于其环保、无毒和优于传统有机溶剂的理化性质而被引入作为新型绿色溶剂。因此，研究它们的物理性质将对应用领域的工艺设计有很大帮助。在这项工作中，以氯化胆碱 (ChCl)、四乙基溴化铵 (TEAB)、四丙基溴化铵 (TPAB) 和四丁基硫酸氢铵 (TBAHS) 为基础，以苯甲酸 (BA) 作为氢键供体 (HBD) 成功制备了四种新型 DESs。作为氢键受体。DES 的物理化学特性，例如密度、声速、电导率、粘度、折射率和表面张力，作为温度的函数进行测量。