Liquid−Liquid Equilibria in Binary Mixtures Containing Fluorinated Benzenes and Ionic Liquid 1-Ethyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)imide

Abstract

Binary liquid−liquid equilibria in mixtures of fluorinated benzenes and ionic liquid, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([emim][Tf2N]), have been measured using the volumetric method over a temperature range from about (283 to 373) K. A general trend between the magnitude of the dipole moment (polarity) and the miscibility was found, although other intermolecular interactions (higher-order moments, π-electron effects, and hydrogen bonding) may also be playing a role for a more detailed trend. The fluorinated benzenes having the largest dipole moments (1,2-difluorobenzene, 1,2,3,4-tetrafluorobenzene, and 1,2,3-trifluorobenzene) were completely miscible in the [emim][Tf2N]. The binary systems (1,4-difluorobenzene, 1,3,5-trifluorobenzene, and 1,2,4,5-tetrafluorobenzene) with zero dipole moments, and the binary systems (1,2,4-trifluorobenzene, fluorobenzene, 1,3-difluorobenzene, pentafluorobenzene, and 1,2,3,5-tetrafluorobenzene) with dipole moments of about 1.4 D were only partial...