Multi-stage Level Reactive Azeotropy

Based on the graphical estimation of reactive azeotropes. Prey and Stichlmair (1999a) establishes the following rules of thumb, 

A practical limitation of this method is imposed by its graphical nature. Thus, this method has been only applied to systems of three components at the most undergoing a single reaction. Extending this method to systems with ric 3 might not be feasible due to the physical limitation of plotting the full-component composition space. 

From a different and more rigorous perspective, a reactive azeotrope might be characterized by the satisfaction of the following necessary and sufficient conditions for a system undergoing a single equilibrium chemical reaction (Barbosa and Doherty, 19876  

It is relevant to point out that the azeotropy expression 2.17 also applies to the last component (n-c) as may be verified by knowing that -1 ° x = y = 1 (Barbosa 

These necessary and sufficient conditions for reactive azeotropes have been generalized and theoretically established for the case of multicomponent mixtures undergoing multiple equilibrium chemical reactions by Ung and Doherty (19956). The starting point for their analysis is the introduction of transformed compositions. It is widely recognized that mole fractions are not the most convenient measures of composition for equilibrium reactive mixtures, as they might lead to distortions in the equilibrium surfaces (Barbosa and Doherty, 1988a Doherty and Buzad, 1992). In order to visualize in a much more 

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