: Mixture Regression

The regression add-on for mixture properties allows extended parameter fitting, calculation and graphical representation options for VLE, HPV, h^E, LLE and AZD ( g^E models, equations of state, electrolyte models).

These regressions are usually focused on one or more data sets of a specific data type (VLE, h^E, ...). For simultaneous regression of different mixture data types, see DDBSP-Recval. Only some of the different regression programs are shown below for selected data types.

VLE Data Regression

In case of VLE data, the regression outputs a page identical to the format used in the DECHEMA Chemistry Data Collection - Vapor liquid Equilibrium Data. Certain default settings are used and two different consistency tests are applied for complete VLE data. Binary interaction parameters for the models Margules, Van Laar, Wilson, NRTL and UNIQUAC are reported. During the regression, the pure component vapor pressure equations are shifted to exactly match the pure component values reported by the author. In addition, mixing rule parameters for the SRK and PR equations of state can be regressed. Final parameters can be exported to the parameter data bank ParamDB.

Besides this output, different graphical representations are available (Fit/Plot).

LLE Data Regression

Simultaneous LLE data regression is available for any number of binary or ternary data sets. The programs employ complex multistep regression strategies to ensure convergence. Examples for binary and ternary regression results are shown below:

SLE Data Regression

Simultaneous regression of binary eutectic solid-liquid equilibrium data is available for any number of binary data sets. An example for the mixture 1-butanol - benzene using NRTL is shown in the following diagram: