The UNIFAC method (UNIFAC Functional-group Activity Coefficient) was developed by Fredenslund et al. A precise description of the dependence on temperature, pressure and composition in multicomponent systems requires reliable thermodynamic models that allow calculation of these properties from available experimental data. The real behavior of fluid mixtures can be calculated with the help of activity coefficients or fugacity coefficients. Because there is little change in the distribution ratio for moderate variations in the acid concentration of dilute solutions, the acetic acid concentrations are not shown in Table 1. Selected distribution ratios (D 2) and selectivities taken from several papers are shown in Table 1. 2001).ДЄ lot of solvents have been examined for extraction of acetic acid. Recovery of organic acids from dilute solutions resulting from fermentation processes is important, and many solvents have been tried in attempts to improve recovery (Upchurch and Van Winkle, 1952 Correa et al., 1989 Sayar et al., 1991 Kirk and Othmer, 1992 Dramur and TatlД±, 1993 Briones et al., 1994 Arce et al., 1995 Fahim et al., 1996 Fahim et al., 1997 SГіlimo et al., 1997 Colombo et al., 1999 Aljimaz et al., 2000 Taghikhani et al. Keywords: acetic acid, butyl acetate, liquid-liquid equilibria.

Distribution coefficients and separation factors were evaluated for the immiscibility region. It was found that UNIFAC group interaction parameters used for LLE did not provide a good prediction. The UNIFAC group contribution method was used to predict the observed ternary liquid-liquid equilibrium (LLE) data. The reliability of the experimental tie-line data was ascertained by using the Othmer and Tobias correlation. Complete phase diagrams were obtained by determining solubility and tie-line data. Abstract - Experimental liquid-liquid equilibria of the water-acetic acid-butyl acetate system were studied at temperatures of 298.15В± 0.20, 303.15В± 0.20 and 308.15В± 0.20 K.

Depriester chart water