Gravimetric measurement of adsorption from binary gas mixtures

Abstract

A precise experimental method for studying binary vapor-liquid equilibrium is to measure total pressure (P) as a function of the mole fraction in the liquid phase (x). The mole fraction in the vapor (y) is calculated from isothermal P-x experimental data using the Gibbs-Duhem equation. A similar procedure for adsorption is to measure total mass (m) of gas adsorbed as a function of the mole fraction in the vapor phase (y). Then the composition of the adsorbed phase is calculated from isothermal m-y experimental data using the Gibbs isotherm. Only a few experimental points are needed for the mixture. The method is rigorous even when the adsorbed phase is nonideal. © 1989, Walter de Gruyter. All rights reserved.