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Local compositions and local surface area fractions: A theoretical discussion
Author(s) -
Panayiotou C.,
Vera J. H.
Publication year - 1981
Publication title -
the canadian journal of chemical engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.404
H-Index - 67
eISSN - 1939-019X
pISSN - 0008-4034
DOI - 10.1002/cjce.5450590416
Subject(s) - uniquac , constraint (computer aided design) , surface (topology) , composition (language) , component (thermodynamics) , mathematics , expression (computer science) , computer science , physics , chemistry , thermodynamics , geometry , activity coefficient , philosophy , aqueous solution , non random two liquid model , linguistics , programming language
The basic constraint for any valid expression for local composition, derived by McDermott and Ashton, is shown to be equivalent to the conservation equation used in Flemr's analysis. A similar constraint for local surface fractions is derived. The applicability of quasi‐chemical expressions for local composition or local surface area fractions is extended to different existing (random) models of solutions. Chao's and Kehiaian's treatments appear as special cases. The statistical thermodynamic derivation of UNIQUAC is discussed in the framework of the generalized treatment. A method for solving the quasi‐chemical equations for quaternary systems is described.