Separation of carbon monoxide from nitrogen-contaminated gaseous mixtures also containing hydrogen and methane

摘要

Carbon monoxide is separated from a gaseous mixture containing hydrogen and methane and contaminated with nitrogen by scrubbing carbon monoxide from a vapor portion of the feed by a liquid methane wash; stripping dissolved hydrogen from the resultant CO-loaded liquid methane stream; fractionating the resultant hydrogen-stripped CO-loaded liquid methane stream to separate nitrogen therefrom; and fractionating the resultant nitrogen-freed bottoms liquid into CO product overheads vapor and methane bottoms liquid. If the gaseous mixture also contains argon, argon content can be removed with the methane content to obviate a separate argon-separation stage as required by prior art processes.