Vapor pressure measurement and correlation of acetonitrile+1-butyl-3-methylimidazolium chloride,+1-butyl-3-methylimidazolium tetrafluoroborate,and+1-hexyl-3-methylimidazolium chloride

Vapor pressures were measured for acetonitrile +1-butyl-3-methylimidazolium chloride (C₄mim]Cl]), +1-butyl-3-methylimidazolium tetrafluoroborate (C₄mim]BF₄]) and +1-hexyl-3-methylimidazolium chloride (C₆mim]Cl]) at temperatures of 313 to 353 K by a quasi-staticmethod. The experimental data for the binary systemswere correlated by the non-randomtwo liquid (NRTL) equationwith an average absolute relative deviation (AARD) of within 1.84%. The results indicate that the three ionic liquids (ILs) can result in a negative deviation from the Raoult's law for the binary solutions containing acetonitrile, and the affinity between ILs and acetonitrile molecules follows the order C₄mim]BF₄]+acetonitrile > C₄mim]Cl]+acetonitrile > C₆mim]Cl]+acetonitrile.