Patent ID: 6113869
Filing Date: 2000-09-05
Classification: B01D,C01B,Y02C,Y02P

Abstract:
A method of purifying an inert gas stream containing water vapor, one or both of carbon monoxide and hydrogen and one or both of nitrogen and methane comprising the steps:(a) removing water vapor from said gas stream and raising the temperature of the gas stream by contacting it with a desiccant;(b) contacting the gas stream from step (a) with oxidation catalyst selected from the group consisting of metal oxide catalyst, noble metal catalyst and mixtures of these in the presence of oxygen in excess of the amount necessary to oxidize all carbon monoxide and hydrogen in said gas stream to carbon dioxide and water, thereby producing and further heating a substantially carbon monoxide- and hydrogen-free gas stream;(c) removing water vapor and/or carbon dioxide from said gas stream from step (b) by contacting the gas stream with water-selective and/or carbon dioxide-selective adsorbent, thereby producing and further heating, a substantially water vapor-free and carbon dioxide-free gas stream(d) removing excess oxygen from said heated substantially water vapor-free and carbon dioxide-free gas stream by chemisorption with a metal agent at a temperature of at least 75.degree. C.; and(e) adsorbing nitrogen and/or methane from said gas stream by contacting the gas stream with an adsorbent selective for nitrogen and methane at a temperature in the range of about 173 K and 93 K.