Effects of adsorbate properties on adsorption mechanism in a carbon molecular sieve

The adsorption characteristics of six pure components (N-2, O-2, Ar, CO, H-2, and CH4) on a CMS were studied over a wide pressure range up to 15 atm by using a volumetric method. Despite only relatively small differences in the kinetic diameters of the probe molecules used, very large differences in the magnitude of apparent time constants were observed. The adsorption kinetic characteristics of six components on the CMS were affected by the relative importance of atomic/molecular size, shape, and polar properties. Especially, the interaction properties of adsorbate molecules were proposed as an important factor to estimate the relative adsorption rate.