The determination of the existence and composition of homogeneous azeotropes
is important both from both theoretical and practical standpoints in the
analysis of phase behavior and in the synthesis and design of separation systems.
We present here a new method for reliably locating any and all homogeneous
azeotropes for multicomponent mixtures. The method also verifies the
nonexistence of homogeneous azeotropes if none are present.
The method is based on interval analysis, in particular an
interval Newton/generalized bisection algorithm that
mathematical and computational guarantee that all azeotropes are located.
The technique is
general purpose and can
be applied in connection with any thermodynamic models.
We illustrate the technique here in several example problems
using the Wilson, NRTL, and UNIQUAC activity coefficient models.
AIChE J., 44, 1745-1755 (1998)