Influence of Temperature on Liquid–Liquid Equilibrium of Methanol + Aromatic + Isooctane Ternary Systems

Abstract

The influence of temperature on the miscibility of the {methanol + p-xylene + isooctane} and {methanol + benzene + isooctane} ternary systems at atmospheric pressure are investigated. The effect of temperature on the phase equilibrium is discussed for each system. All chemicals are verified using gas chromatograph, density, viscosity and refractive index. Phase equilibrium are reached using a modified version of measurement equipment used previously. Some ternary systems and binary subsystems are taken from the literature at different temperatures to determine the influence of the temperature on the systems. The upper critical solution temperature for the methanol + isooctane binary system was determined by the constant-composition method with an accuracy of ± 0.1 K. Experimental data are compared with the literature. Calculated values by the non-random two liquids (NRTL) and universal quasi-chemical (UNIQUAC) equations are contrasted with experimental data for the ternary systems. Deviations from the experimental binodal curve have good adjustment of less than one per cent for all systems.