Liquid–liquid equilibria for the water + ethanol + 2-ethyl-1-hexanol ternary system at several temperatures
Liquid–liquid equilibrium data for the system water + ethanol + 2-ethyl-1-hexanol were obtained at 298.15, 308.15, and 318.15 K. Data for the binodal curves have been determined by cloud-point method and conjugate points on tie-line were obtained by correlating the refractive index of the binodal curves as a function of composition. The tie-line data at each temperatures were satisfactorily correlated using the method of Othmer and Tobias and the plait points coordinates were estimated. The experimental data were also fitted with the UNIFAC group contribution method for the activity coefficients using the isoactivity conditions as restraint equations. From the experimental results, ethanol extraction by 2-ethyl-1-hexanol appears not to depend on temperature and 2-ethyl-1-hexanol could be selected as a promissory solvent for extraction of ethanol from aqueous solutions. Keywords: liquid–liquid equilibria, ethanol extraction, water + ethanol + 2-ethyl-1-hexanol ternary system.