Separation of oxygen argon mixture by pressure swing adsorption (PSA)

Abstract

Four adsorbents for the separation of oxygen-argon mixture by kinetically controlled PSA were compared based on adsorption equilibrium and kinetics measured in the linear range. The equilibrium and kinetics of argon in the chosen adsorbent, Takeda II Carbon Molecular Sieve (CMS), were measured at an elevated pressure range up to 6 bar. PSA experiments were carried out to concentrate argon from an oxygen-argon mixture (95: 5 based on mole fraction) using a single-bed, 3-step cycle operated in 0-3 atm pressure range. PSA simulations were conducted using a bidispersed PSA model including the dual transport resistance with strongly concentration dependent transport parameters to capture the experimental phenomena of the system featured by kinetically controlled separation, high proportion of faster component in the feed mixture and vacuum operation. The performance of the single-bed, 3-step cycle at different operation conditions was studied using the PSA simulation model validated by experimental results. The feasibility of other two cycles was also studied through numerical simulation.