Separation of the Chlorofluorocarbon (CFC) CCl2F2 from N2 in NaY Zeolite, in MIL-127(Fe) and in the two Carbon Nanotubes CNT (9,9) and CNT (11,11)

Four well-suited porous materials for the selective adsorption of the most prominent CFC, which is CCl2F2, from the air are carbon nanotubes CNT (9,9) and CNT (11,11), NaY zeolite, and the Metal Organic Framework MIL-125(Fe). The adsorption has been investigated through molecular simulations. Simulation results and theoretical considerations show that reasons for the extraordinarily high selectivity in all four cases were found to be the differences in the enthalpy of adsorption for the various adsorbed gases rather than steric reasons. The four adsorbate–adsorbent systems have been examined at different temperatures, pressures, and concentration ratios in the mixture. Among them, the carbon nanotube CNT (11,11) exhibited the highest selectivity, reaching up to 104.