Ionic liquids have received increasing attention for their potential uses as non-volatile separation and reaction solvents
and the liquid-liquid equilibrium(LLE)of ionic liquid containing systems is of great importance for such practical applications.The NRTL(non-random two liquid)equation was extended and used in this paper for the calculation of the LLE data of some ionic liquid-alcohol binary systems.It was found that the extended NRTL model could be accurately used to represent the LLE of these ionic liquid-alcohol systems with the average absolute deviations lower than 0.6%.The LLE data of two ternary systems
H2O-n-butanol-[bmim]PF6 and H2O-n-butanol-[omim]PF6
were further successfully predicted for the first time by using the NRTL binary parameters.