It is important to determine the existence and composition of homogene
ous azeotropes in the analysis of phase behavior and in the synthesis
and design of separation systems, from both theoretical and practical
standpoints. A new method for reliably locating any and all homogeneou
s azeotropes for multicomponent mixtures is presented. The method also
verifies the nonexistence of homogeneous azeotropes if none are prese
nt. The method is based on interval analysis, in particular an interva
l-Newton/generalized-bisection-algorithm providing a mathematical and
computational guarantee that all azeotropes are located. This general-
purpose technique can be applied in connection with any thermodynamic
models. The technique is illustrated in several example problems using
the Wilson, NRTL, and UNIQUAC activity-coefficient models.