Abstract: Carbon monoxide - containing gas streams are passed over a catalyst to deposit a surface layer of active surface carbon thereon essentially without the formation of inactive coke. The active carbon is subsequently reacted with steam or hydrogen to form methane. Surprisingly, hydrogen and water vapor present in the feed gas do not adversely affect CO utilization significantly, and such hydrogen actually results in a significant increase in CO utilization.

Abstract: Carbon monoxide-containing gas streams are passed over a catalyst capable of catalyzing the disproportionation of carbon monoxide so as to deposit a surface layer of active surface carbon on the catalyst essentially without formation of inactive coke thereon. The surface layer is contacted with steam and is thus converted to methane and CO.sub.2, from which a relatively pure methane product may be obtained. Dilute carbon monoxide-containing streams, as from underground coal gasification with air or the effluent from blast furnace operations, can be used without pretreatment to convert the carbon monoxide and/or to separate inert gases therefrom. Conversion of the active surface carbon with high pressure steam enables a high pressure product methane stream to be generated without expensive compression equipment and high energy consumption. Nickel, cobalt, iron, ruthenium, rhenium and alloys thereof are preferred catalysts, with the surface area thereof being preferably at least about 10 m.sup.2 /gr.