Vacancy solution theory of adsorption using Flory‐Huggins activity coefficient equations

Abstract

New equations for the physical adsorption of gases on solids have been developed based on the vacancy solution model of adsorption in conjunction with the Flory‐Huggins activity coefficient equations. The isotherm equation contains three regression parameters: a Henry's law constant, the limiting amount of adsorption, and a gas‐solid interaction term. Pure‐gas data over a range of temperature can be correlated using only five parameters. Gas‐mixture equilibria can be predicted using only the parameters obtained from the pure‐gas data. Pure‐component, binary, and ternary adsorption equilibrium data on activated carbons, silica, and zeolites over a wide range of conditions have been used to evaluate the model. The results show that, except for a few systems, this model predicts gas‐mixture equilibria better than any other model.