Pressure swing adsorption for CO2/N2 and CO2/CH4 separation: Comparison between activated carbons and zeolites performances

The main advantage of ACs is its full reversibility after regeneration by pressure modulation. At pressure above 4 bars, the adsorption capacities of ACs are greater than those of zeolites. In the case of gas separation, results indicate that it is possible to obtain a fairly pure gas during the adsorption phase for the two studied mixtures. In particular it was observed that for the CH4-CO2 mixture the adsorption yielded an efficient separation with a concentration of more than 95% of CH4 in the purified gas.