title: In situ crystallization of ionic liquid [Emim][PF6] from methanol solution under high pressure.
abstract: The solubility of 1-ethyl-3-methylimidazolium hexafluorophosphate ([Emim][PF6]) in methanol under high pressure is newly measured quantitatively according to the correlation between the ratios of Raman intensity and the concentrations. In situ crystallization and cation conformation of [Emim][PF6] from methanol solution under high pressure have been investigated by using Raman spectroscopy in detail. Remarkably, crystal polymorphism was observed and two crystalline phases (phases I and II) coexisted under high pressure up to ∼ 1.4 GPa. However, only phase II was obtained by recrystallization at ∼ 2 GPa. Our findings may facilitate the development of an effective way for crystallization and purification of ionic liquids under high pressure.
authors: The High Pressure Research Center of Science and Technology, Zhengzhou University of Light Industry , Zhengzhou, 450002, China.
authors: Haining
authors: H
authors: Li
authors: Lei
authors: L
authors: Su
authors: Xiang
authors: X
authors: Zhu
authors: Xuerui
authors: X
authors: Cheng
authors: Kun
authors: K
authors: Yang
authors: Guoqiang
authors: G
authors: Yang