Highlights of non-equilibrium, non-isobaric, non-isothermal desorption of nitrogen from a LiX zeolite column by rapid pressure reduction and rapid purge by oxygen

The effects of adsorption kinetics, column pressure drop, gas phase mass and heat dispersions, gas-solid heat transfer resistance, and adsorber adiabaticity on desorption of N-2 from a LiX zeolite column by O-2 purge as well as pressurization-depressurization of the column using pure N-2 were recently studied using a numerical model of these processes [Chai et al. in Ind Eng Chem Res 50:8703, 2011, Chai et al. in Adsorption 18:87, 2012, Chai et al. in AIChE J 59:365 2013; Rama Rao et al. in Adsorption 2013]. The role of adsorbent particle size and column length to diameter ratio in determining the durations and efficiency of these processes were also investigated. These studies revealed several important limiting and optimum conditions for optimum operation of these processes which can be useful in design of a practical rapid pressure swing adsorption (RPSA) process for medical oxygen concentrator (MOC) application. The purpose of this short review article is to consolidate and re-emphasize these important results in a single article to be used as a guideline for design of a RPSA-MOC unit.