A novel process is disclosed which produces a CO-rich stream from a stream containing hydrogen, carbon monoxide, methane, and components heavier than methane. The process utilizes a combined CO purification and demethanizer column (5) which reduces the overall capital cost of the process, and efficient heat integration which reduces the energy required by the process. This process is useful in recovering a CO-rich stream (10) from the effluent (1) of an autothermal cracking reactor. It is particularly useful when one or more of the heavy components (6) has a higher value as pure product than when admixed with methane (11), and when product of a purified hydrogen stream (8) is also desirable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 This invention was made with government support under United States Department of Energy Cooperative Agreement No. DE-FC07-01ID 14090.