Adsorption isotherms were measured for pure nitrogen, oxygen, and their binary mixtures (20%, 40%, and 60% nitrogen in the mixture) on a commercial zeolite 5A. The measurements were conduced using a volumetric method at temperatures of (273, 283, 303, and 343) K and at pressures to 950 kPa. The 2D equations of state of van der Waals, Soave-Redlich-Kwong, Peng-Robinson, and Eyring have been applied to represent total adsorption for the pure and binary systems. The amount of adsorption of each component has been obtained in the mixture as well as the selectivity by thermodynamic prediction. Experimental results indicate a very good agreement with thermodynamic modeling and with some current results in the literature.