Analytical solution of groups ASOG

UNIFAC andASOG Development. Pertinent equations of the UNIQUAC functional-group activity coefficient (UNIFAC) model for prediction of activity coefficients including example calculations are available (162). Much of the background of UNIFAC involves another QSAR technique, the analytical solution of groups (ASOG) method (163). 

When experimental equilibrium data on nonideal mixtures are not available, methods such as those based on Derr and Deal s analytical solution of groups (ASOG) [28] or the UNIFAC correlation (discussed in Example 3.4) may be used. Activity-coefficient estimation methods are also available in various thermodynamic-data packages, such as Chemshare. Further discussion may be found in Prausnitz [3] and in Reid, Prausnitz, and Sherwood [1]. 

In the analytical solution of groups (ASOG) method of Derr and Deal [14], the four postulates of Wilson and Deal are implemented. The activity coefficient due to molecular size differences is given by the Flory-Huggins equation, Equation (4.414), and the group activity coefficient is given by the Wilson equation. 

The analytical-solution-of-groups (ASOG) method was developed by Derr and Deal17 and Wilson,72 and a compilation of parameters has been prepared by Kojima and Tochigi.41 In this method, the activity coefficient of component / in a mixture is computed as follows... 

The first group contribution method for the prediction of VLE (activity coefficients) was the so-called analytical solution of groups (ASOG) method [50, 51], developed within Shell. The ASOG method uses the Wilson model to describe the concentration dependence of the group activity coefficients required in the solution of groups concept. 

Correa, A., Comesana, J., Sereno, A. (1994). Use of analytical solutions of groups (ASOG) contribution method to predict water activity in solutions of sugars, polyols and urea. International Journal of Food Science and Technology, 29, 331-338. 

Several methods of group contributions have been developed Analytical Solution of Groups (ASOG) [WIL 62], Universal Quasichemical... 

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