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Fugacity of a Single Component: Screencasts

Explains why fugacity is important for single components and tells how it is used.

We suggest you list the important points in this screencast as a way to increase retention.

Explains how fugacity for a single component changes with temperature and pressure. Uses an interactive simulation to demonstrate the fugacity behavior.

We suggest you list the important points in this screencast as a way to increase retention.

Optional screencast: Fugacity Temperature Dependence: Single Component

Important Equations:

Antoine equations for component \(i\):

\[log_{10}(P^{sat} _i) = A_i – \frac{B_i}{C_i +T}\]

where \(P^{sat} _i\) is the saturation pressure
\(T\) is the temperature (most often in °C)
\(A_i, B_i,\) and \(C_i\) are constants for a given component, \(i\)

Fugacity of liquid at elevated pressure (Poynting correction):

\[f = \phi ^{sat}P^{sat}exp\left( \frac{V^L(P – P^{sat})}{RT}\right)\]

where \(V^L\) is the molar volume of the liquid
\(\phi ^{sat}\) is the fugacity coefficient at saturation pressure
\(P\) is the pressure
\(R\) is the ideal gas constant
\(T\) is the absolute temperature

Fugacity of solid using Poynting correction:

\[f = \phi ^{sat}P^{sat}exp\left( \frac{V^S(P – P^{sat})}{RT} \right) \]

where \(V^S\) is the molar volume of the liquid.

Vapor-liquid phase equilibrium:

\[f^L = f^V\]

where \(f^L\) is the fugacity of the liquid
\(f^V\) is the fugacity of the vapor

Gibbs free energy departure function \(G – G^{ig}\):

\[\frac{G – G^{ig}}{RT} = ln \left( \frac{f}{P} \right) = ln(\phi )\]

where \(f\) is the fugacity
\(\phi \) is the fugacity coefficient, \(\frac{f}{P}\)