Inverted pressure swing adsorption process

Claim 1

A cyclic inverted pressure swing adsorption process for enhancing the purity of the readily adsorbable gas component recovered from a gas mixture of said gas component with a less readily adsorbable gas component comprising: (a) introducing said gas mixture at a first, low pressure to an adsorption column containing an adsorbent capable of selectively adsorbing the readily adsorbable gas component therefrom, the less readily adsorbable gas component of the mixture being adsorbed at said low pressure, displacing and depleting the more readily adsorbable gas component in the adsorbed phase, resulting in an advancing gas phase zone of said readily adsorbable gas component preceding a gas phase zone containing both readily and less readily adsorbable gas components; (b) increasing the pressure in said column to a second, high pressure causing selective adsorption of the readily adsorbable gas component, thereby depleting said component in the gas phase and enriching said gas phase in the less readily adsorbable gas component; (c) purging the column with said readily adsorbable gas component at said high pressure to remove said gas phase enriched in the less readily adsorbable gas component from said column; (d) depressurizing said column from said high pressure, the depressurization resulting in a release of the readily adsorbable gas component from the adsorbent; and (e) repeating said steps (a)-(d) on a cyclic basis with additional quantities of said gas mixture, whereby the inverted pressure swing adsorption cycle results in an increased adsorption of the more readily adsorbable gas component by the adsorbent at high pressure and increased separation of said component from the less readily adsorbable gas component at said high pressure, enhancing the purity of said readily adsorbable gas component recovered upon depressurization of the column following the convenient purging of the less readily adsorbable gas component therefrom.