Non-random two-liquid model
The non-random two-liquid model (abbreviated NRTL model) is an activity coefficient model introduced by Renon and Prausnitz in 1968 that correlates the activity coefficients γ i {\displaystyle \gamma _{i}} of a compound with its mole fractions x i {\displaystyle x_{i}} in the liquid phase concerned. It is frequently applied in the field of chemical engineering to calculate phase equilibria.
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