S. Dunnebeil et al., COMPARISON OF 2 PREDICTIVE G(E) MODELS FOR VAPOR-LIQUID-EQUILIBRIUM CALCULATIONS, Chemical engineering journal and the biochemical engineering journal, 61(1), 1996, pp. 21-26
Ash (S.N. Ash, P. Ray and B.V. Detta, AIChE J., 31 (1985) 821; S.N. As
h, Chem. Eng. J., 48 (1992) 183) has proposed a correlation for calcul
ating the binary parameters of the Wilson g(E) model by using only pur
e-component parameters: solubility parameters, molar liquid volumes, r
elative van der Waals volumes and surfaces, critical properties, acent
ric factors and dipole moments. To evaluate the Ash correlation the va
pour-liquid equilibria for 75 binary systems, activity coefficients at
ininite dilution and excess enthalpies were predicted and compared wi
th experimental data and with the modified UNIFAC model (J. Gmehling,
J. Li and M. Schiller, Ind. Eng. Chem. Res., 32 (1993) 178). It was fo
und that the correlation of Ash and coworkers is significantly inferio
r to the modified UNIFAC model and cannot be recommended for phase equ
ilibrium predictions for those cases where UNIFAC parameters are avail
able.