On the Combinatorial Part of the UNIFAC and UNIQUAC Models

I. Kikic, P. Alessi, Peter Rasmussen, Aage Fredenslund

Research output: Contribution to journalJournal articlepeer-review

Abstract

The excess Cibbs energy of liquid mixtures may be predicted using group contribution models (f.ex. UNIFAC and ASOG), or it may be correlated using molecular models such as UNIQUAC. Group contribution models and the UNIQUAC model contain a combinatorial contribution which accounts for size- and shape-effects and a residual contribution which accounts for interactions among groups or molecules. A new expression for the combinatorial contribution is given which yields much improved predictions of the excess Gibbs energy of systems where the residual contribution may be expected to be zero (e.g., mixtures of aliphatic hydrocarbons). It is shown that it is advantageous to incorporate the new combinational expression into future modifications of the UNIFAC model.
Original languageEnglish
JournalCanadian Journal of Chemical Engineering
Volume58
Issue number2
Pages (from-to)253-258
ISSN0008-4034
DOIs
Publication statusPublished - 1980

Fingerprint

Dive into the research topics of 'On the Combinatorial Part of the UNIFAC and UNIQUAC Models'. Together they form a unique fingerprint.

Cite this