Equilibrium Adsorption of Multicomponent Gas Mixtures at Elevated Pressures

Equilibrium adsorption of H₂, CO, CH₄, C0₂, and H₂S (single and mixed gases—two to five species) was measured on activated carbon at pressures up to 400 psia. Temperature-dependent parameters, regressed from single-gas data, were applied to four theoretical models which predict adsorption from gas mixtures. Deviations between theory (IAS) and experiment increased with pressure and with the number of components in the mixture. Furthermore, none of the theories employing only single-gas data could consistently predict multicomponent adsorption. It was found, however, that multicomponent adsorption could be predicted from the extended Langmuir equation by including an interaction parameter calculated from only single and binary data. An unusual result of this work was that in the application of mixture adsorption theories, it was shown that from the same model significantly different results can be obtained depending on the selection of the independent variable set, {T, P, X_i} or {T, P, Y_i-}.