EQUILIBRIUM AND KINETICS OF ADSORPTION OF FREON-12 AT INFINITE DILUTION

Equilibrium and kinetic data for adsorption of trace CF2Cl2 (Freon-12) from various carrier gases on BPL activated carbon are reported. Coad sorption of the bulk carrier gas can severely reduce the equilibrium a dsorption capacity and adsorptive mass-transfer coefficient of strongl y adsorbed CF2Cl2. The difference in size between CF2Cl2 and the bulk carrier gas molecules plays a major role in establishing the binary or multicomponent equilibrium adsorption properties. The multisite (sing le and multicomponent) Langmuir model, which accounts for differences in adsorbate sizes, provides a reasonable framework for describing the size effects. The adsorptive mass transfer of CF2Cl2 under the experi mental conditions investigated is dominated by surface diffusion into the pores of the activated carbon. The surface diffusivity is a strong function of the extent of coverage and strength of adsorption of the bulk components.