Dynamic Adsorption Behaviors of Various Zeolites for the Adsorbent of Air Separation by Pressure-swing Adsorption Method

Abstract

Adsorption behaviors of O₂ and N₂ in pressure-swing adsorption (PSA) at lower temperature on various American natural zeolites and synthetic zeolites having different pore structures were studied. The adsorption properties were largely dependent on whether the dimension of the pore-structure connection is one or three. Molecular sieves MS-5A and MS-4A, which have a large amount of adsorption and a large difference in adsorption capacity for N₂ and O₂, were preferable to air separation by the PSA method. The applicability to the air separation at low temperature was also investigated by using MS-4A and MS-5A as the adsorbent. Highly concentrated N₂ was obtained by MS-5A in the elution period and by MS-4A in the adsorption period. Furthermore, the applicability to the air separation at room temperature was examined by using MS-4A as the adsorbent, and the separation was confirmed at this condition.