Patent ID: 6849106
Filing Date: 2005-02-01
Classification: B01D,C01B,Y02C,Y02P

Abstract:
1. A pressure swing adsorption process (PSA) for the purification of a hydrogen gas mixture containing contaminants comprising carbon monoxide and nitrogen and optionally at least one of carbon dioxide, water and C 1 -C 8 hydrocarbons, comprising an adsorption region containing an inlet and outlet and the following successive stages: a) passing said hydrogen gas mixture into the adsorption region comprising: b) in a desorption stage, desorbing the carbon monoxide, nitrogen and possible other impurities adsorbed on the absorbents by providing of a pressure gradient and gradual lowering of the pressure in said adsorption region, so as to recover the carbon monoxide, nitrogen and optionally other impurities via the inlet of said adsorption region; and c) raising in pressure said adsorption region by the introduction of a stream of pure hydrogen via the outlet of the adsorption region, said process resulting in a substantially enhanced relative productivity compared to a process wherein the only difference is that the second and third adsorbent are the same and being either CaA or CaX, said relative productivity being calculated at stationary conditions for a hydrogen yield of 80% and a hydrogen purity of 99.999%.