In this work, 16 kinds of [FeCl_4]^--based magnetic ionic liquids(ILs) with different cation structures have been designed and synthesized, and their structures are characterized by IR and Raman spectroscopy. Then the...In this work, 16 kinds of [FeCl_4]^--based magnetic ionic liquids(ILs) with different cation structures have been designed and synthesized, and their structures are characterized by IR and Raman spectroscopy. Then the lower critical solution temperature(LCST)-type phase behavior of these magnetic ILs in water is investigated as a function of concentration. It is shown that cation structure, alkyl chain length and molar ratio of FeCl_3/chloride IL have a significant influence on the LCST of the mixtures. The phase separation temperature can be tuned efficiently by these factors. Meanwhile, the LCST-type phase separation process is also investigated by dynamic light scattering. The results support the mechanism that the hydrogen bonds of the [FeCl_4]^- anion with water have been gradually disrupted to form ILs aggregates with increasing temperature. In addition, the stability of the ILs in water is also examined in some details. These LCST-type phase separation systems may have potential applications in extraction and separation techniques at room temperature.展开更多
基金supported by the National Natural Science Foundation of China (21473050, 21403060)Program for Innovative Research Team in Science and Technology in University of Henan Province (16IRTSTHN002)+1 种基金Plan for Scientific Innovation Talent of Henan Province of China (144200510004)the Natural Science Research Program of Henan Educational Committee (2010A150014)
文摘In this work, 16 kinds of [FeCl_4]^--based magnetic ionic liquids(ILs) with different cation structures have been designed and synthesized, and their structures are characterized by IR and Raman spectroscopy. Then the lower critical solution temperature(LCST)-type phase behavior of these magnetic ILs in water is investigated as a function of concentration. It is shown that cation structure, alkyl chain length and molar ratio of FeCl_3/chloride IL have a significant influence on the LCST of the mixtures. The phase separation temperature can be tuned efficiently by these factors. Meanwhile, the LCST-type phase separation process is also investigated by dynamic light scattering. The results support the mechanism that the hydrogen bonds of the [FeCl_4]^- anion with water have been gradually disrupted to form ILs aggregates with increasing temperature. In addition, the stability of the ILs in water is also examined in some details. These LCST-type phase separation systems may have potential applications in extraction and separation techniques at room temperature.
