Solid-Liquid Equilibrium of Binary Systems Containing Selected
Ionic Liquids
Ying-Tzu Hone, Hsin-Yi Tien, Ho-mu Lin, Ming-Jer Lee*
Department of Chemical Engineering, National Taiwan University of Science and Technology,
43 Keelung Road, Section 4, Taipei 106-07, Taiwan
mjlee@mail.ntust.edu.tw
Abstract
The solid-liquid equilibrium (SLE) data were measured for seven binary systems composed of
one of four ionic liquids, [Emim][PF6], [Emim][ETSO4], [Bmim][MDEGSO4], and
[Bmim][BF4] with water, adipic acid, succinic acid, benzoic acid, or ethyl benzoate by using
the solid-disappearance method. Experimental results showed that each binary behaved as a
simple eutectic system. Moreover, three-phase (solid-liquid-liquid) coexistence was also
found in [Emim][PF6] + water and [Bmim][BF4] + ethyl benzoate systems within the
composition range of 0.05 to 0.94 in the weight fraction of [Emim][PF6] and 0.091 to 0.420 in
the mole fraction of [Bmim][BF4], respectively. The SLE data can be correlated satisfactorily
with the NRTL model for each binary system. Using the parameters determined from the SLE
data, we found that the NRTL model was capable of qualitatively estimating the compositions
of two coexistent liquid phases at solid-liquid-liquid equilibrium (SLLE).
* Presenter. This paper is submitted for poster presentation.