(725b) Equilibrium Adsorption Of Nitrogen, Oxygen and Their Binary Mixtures On Pelletized LiX Zeolite

New pure gas and binary gas mixture adsorption isotherms of nitrogen and oxygen were measured on a pelletized sample of LiX zeolite in the pressure range of 0 – 6 atmospheres at 273.1, 303.1 and 338.1^oK by employing an isothermal column dynamic method. Measurements included low pressure isotherm data in order to establish the Henry’s law regions.  The data show that the zeolite exhibits significant energetic heterogeneity for adsorption of these gases. A pure and mixed gas heterogeneous isotherm model was successfully used to describe the experimental data. Constraints imposed on the model parameters by adsorption thermodynamics and Henry’s law were obeyed in course of the data fit.

It is shown that adsorbent heterogeneity plays a significant role in determining the mixed gas adsorption characteristics for this system. A homogeneous isotherm model may empirically fit the pure gas isotherms fairly well but such a model will be very misleading in estimating mixed gas isotherm data.