Reactive liquid–liquid extraction (RLLE) was applied for the removal of 2,4-dichlorophenoxyacetic acid (2,4-D) from its aqueous solution. Deep eutectic liquids (DELs) was used as extractant in a conventional solvent (diethyl succinate-DES) through RLLE. Various menthol-based DELs were prepared. Menthol was used as hydrogen bond acceptor, whilst formic acid and acetic acid were hydrogen bond donor for the DEL preparations. The best 2,4-D removal was achieved by menthol/formic acid (1/2, molar ratio) combination. The menthol-based DEL increased the extraction performance of DES by almost 2–3 times. More than 90% of 2,4-D were extracted by the recommended method with the designed solvent. Thermodynamics study has been also executed. Thermodynamics of the 2,4-D transfer from aqueous phase to hydrophobic phase has been found to be spontenous and endothermic process, which is incentived by entropy. Moreover, Fourier transformed infrared-attenuated total reflectance was used for the characterization reasons of the prepared DELs. Additionally, physical properties such as pH, density, viscosity and refractive index of the products were also measured. The last but not the least, viscosity and acidity of the extraction medium were found to be effective parameters.

中文翻译：

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专门设计的基于薄荷醇的深共晶液体，用于通过反应性液-液萃取去除除草剂2,4-二氯苯氧基乙酸

反应性液-液萃取（RLLE）用于从水溶液中去除2,4-二氯苯氧基乙酸（2,4-D）。通过RLLE，在常规溶剂（琥珀酸二乙酯-DES）中将深共晶液体（DELs）用作萃取剂。制备了各种基于薄荷醇的DEL。薄荷醇用作氢键受体，而甲酸和乙酸是DEL制剂的氢键供体。薄荷醇/甲酸（1/2，摩尔比）的组合可实现最佳的2,4-D去除效果。基于薄荷醇的DEL将DES的萃取性能提高了近2-3倍。通过推荐的方法，使用设计的溶剂萃取了90％以上的2,4-D。还进行了热力学研究。2的热力学 已经发现从水相到疏水相的4-D转移是自发的和吸热的过程，这是受熵激励的。此外，由于制备的DEL的表征原因，使用傅立叶变换的红外衰减的全反射率。另外，还测量了产品的物理性质，例如pH，密度，粘度和折射率。最后但并非最不重要的是，提取介质的粘度和酸度是有效的参数。