 ##  [UNIFAC Model](/unifac-model) 

  ##  [UNIFAC Model](https://engineering.quantumdictionary.io/unifac-model-0) 

  
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**Engineering &amp; Applied Technologies Dictionary**

 
Definition

A group-contribution excess Gibbs energy method that estimates activity coefficients by summing contributions of molecular functional groups and their pairwise interaction parameters, enabling prediction of liquid-phase nonideal behaviour when binary experimental parameters are missing.