UNIFAC group interactions parameters

Fig. 4. UNIFAC group interaction parameter matrix, the ISi represents parameters fit and parameters not available (168). A represents an aromatic...

Table 2 UNIFAC group interaction parameters for prediction of vapour-liquid equilibria at temperatures between 250 and 425 K 539...

It should be pointed out that for MHV1 and MR1, the UNIFAC group interaction parameter were obtained with VLE data for C02/n-aikanes up to n-C10FI22 (Holderbaum and Gmehling, 1991), while for LCVM, VLE data up to n-C28H58 were used(Boukouvalas et al., 1994). 

A number of methods based on regular solution theory also are available. Only pure-component parameters are needed to make estimates, so they may be applied when UNIFAC group-interaction parameters are not available. The Hansen solubility parameter model divides the Hildebrand solubility parameter into three parts to obtain parameters 8d, 5p, and 5 accounting for nonpolar (dispersion), polar, and hydrogenbonding effects [Hansen,/. Paint Technot, 39, pp. 104-117 (1967)]) An activity coefficient may be estimated by using an equation of the form... 

The combinatorial and residual terms are obtained from the original UNIFAC. An additional term is added for the FV effects. An approximation but at the same time an interesting feature of UNIFAC-FV and the other models of this type is that the same UNIFAC group-interaction parameters, i.e., those of original UNIFAC, are used. No parameter estimation is performed. The FV term used in UNIFAC-FV has a theoretical origin and is based on the Flory equation of state ... 

Nonideal Compute y-UNIFAC Group interaction parameters Gmehling et al,s... 

Table H.2 UNIFAC group interaction parameters a m (K) for the main groups 1-9.

The following internet site www.ddbst.com contains the entire list of the published UNIFAC group interaction parameters. The revised and extended UNIFAC group interaction parameter matrix is only available for the sponsors of the UNIFAC consortium www.unifac.org. ... 

Table 1.3 UNIFAC group interaction parameters b rn for the main groups -9. 

The following internet site wwui.ddbst.com contains the entire list of the published modified UNIFAC group interaction parameters. 

For most of the structural groups the group interaction parameters of the group contribution equation of state are identical with the UNIFAC group interaction parameters. Therefore only van der Waals properties of a few selected gases are given below. 

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