TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Properties: The reaction portion (A) has entrance reaction temperature of 100-160degrees C, and exist of reaction temperature of 180degrees C or less. Preferred Composition: The IVB group metal is tin. The VIA group metal is molybdenum, and tungsten. The VIIA group metal is manganese and rhenium. The VIII group metal is ruthenium, platinum, palladium, nickel, iron, and cobalt. The metal load of catalyst in reaction portion (A) is 0.5-90 wt.%. The content of ruthenium is 20-90 wt.%. The carbon monoxide adsorption tower is filled with carbon monoxide adsorption agent (0.5-15 wt.%). The carbon monoxide adsorption agent consists of zeolite and metal chosen from IVB group, VIA, VIIA group, and/or VIII group. The zeolite is chosen from ZSM-5 type zeolite, mordenite type zeolite, faujasite type zeolite and/or beta -zeolite. EXAMPLE - Cobalt nitrate hexahydrate (in g) (154.8), aqueous solution of zirconyl nitrate (201.6), nickel nitrate hexahydrate (36.8), water (2500), sodium hydroxide (85.5), and water (1519.5) were added and blended to obtain hydrogel. The obtained hydrogel was cured at 80degrees C, filtered, dried to obtain complex oxide fine particles and molded to form methanation catalyst support. Further, ruhenium chloride (10 wt.%), and obtained methanation catalyst support (50) were added, and dried to obtain a methanation catalyst (A). Water (2200), aqueous solution of zirconyl nitrate (400), sodium hydroxide (65) and water (1321) were added, cured, dried to obtain zirconium-oxide fine particles and molded to obtain methanated catalyst support. The obtained methanation catalyst support (50), and ruthenium chloride (16.2), were added, and dried to a obtain methanation catalyst (B). The obtained methanation catalyst (A) and obtained methanation catalyst (B), and catalyst (4.2 ml) were added and reacted at 120degrees C to obtain methanated carbon monoxide. The methanated carbon monoxide had excellent efficiency in performing methanation reaction, and selectivity at high temperature.