MSE Density Parameter Update

Jump to: navigation, search

In UNIQUAC term, the excess molar volume,Density Term 1.jpg , is assumed to be analogous to that of the excess Gibbs energy, i.e.

Density Term 2.jpg (Combinatorial term omitted)

where Term Term.jpg is a different interaction parameter from that of Term 4.1.jpg in the Term 5.jpg model. The symmetrically normalized T7.jpg(subscript UNIQ is omitted in the following text) needs to be converted to the unsymmetrically normalized value (T8.jpg) for density calculations in MSE. Conversion fromT7.jpgto T8.jpg: Standard state chemical potentials in the two normalizations are related by T9.jpg (or T10.jpg) which is derived from equality of chemical potentials in two normalizations, and using T11.jpg1 in the infinite dilution limit. Derivatives of ’s with respect to pressure give volumes, i.e. T12.jpg -> T13.jpg Here is how to calculate T14.jpg Analogous to T15.jpg, T16.jpg can be defined as T17.jpg and derived from Eq. (1) as: T18.jpg (2a)

At infinite dilution, T19.jpg (2b)

Now,T20.jpg can be calculated from Eq. (3) by combining Eq (1) and (2b):

T21.jpg (3)

In Eq. (1) and (2),

T22.jpg T23.jpg (Correspond to D0JI, D1JI, D2JI) Equation (3) is equivalent to the equation:

T24.jpg, with T25.jpg

Solution volume is then calculated by


Here T8.jpg is calculated from contributions of UNIQUAC and “middle-range” terms, if applicable, and T27.jpg is from either HKF or as described in 2002 paper for organic component.

This was former Tip85