The adsorption equilibria of CO2, on zeolite 13X and zeolite X/activated carbon composite (Zeocarbon) were measured by a static volumetric method. The equilibrium experiments were conducted at (273.15, 293.15, 313.15, 333.15, and 353.15) K and at pressures up to 102.0 kPa for zeclite 13X and 99.7 kPa for Zeocarbon. The experimental data obtained were correlated by the Toth, UNILAN, and Sips models, which are generally used for microporous adsorbents such as zeolites and activated carbon. The isosteric enthalpies of adsorption were calculated for CO2 on both adsorbents.