Core-shell composite adsorbent for use in hydrogen and helium psa processes

Abstract

The invention relates to the intensification of hydrogen PSA processes through utilization of specifically engineered core-shell composite adsorbents. Different embodiments of core-shell adsorbents can be used with either high or low heat capacity cores, and different adsorbent shells (e.g. activated carbon, zeolite, silica gel, alumina etc.) resulting in higher mass transfer rates and hence sharper mass transfer fronts during the PSA process. The location of the limiting impurity front determines the product purity. Therefore, with sharper impurity fronts, lower height of adsorbent bed is required, and cycle time can be proportionally reduced. Also, thermal swing during the PSA can be reduced by use of such adsorbents. The use of a high heat capacity core to reduce the thermal swing, leads to higher overall working capacity of the adsorbent bed.