Calculation of Component Activities for Se-Based Binary Systems by NRTL Equation

The interaction energy parameters of the Nonrandom two-liquid (NRTL) equation for Bi–Se, Pb–Se, Sb–Se, and Tl–Se binary systems were determined. difference in goodness fit between was discussed each system. activities components at corresponding temperatures four calculated using NRTL equation. mixing enthalpies Gibbs free energies these obtained. calculations are agreement with experimental data from literature. It shows that is reasonable accurate based on concept local composition two-fluid theory, especially containing liquid–liquid equilibria. results we obtained can be very useful performing vacuum experiments crude selenium.