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PP-I-27KINETICS OF CO METHANATION OVER SUPPORTEDNICKEL CATALYSTSHuan N.M. 1 , Loc L.C. 1 , Tri N. 1 , Thoang H. 1 , Gaidai N.A. 2 , Nekrasov N.V. 2 ,Agafonov Yu.A. 2 , Lapidus A.L. 21 Institute of Chemical Technology, VAST, Ho Chi Minh, Vietnam2 N.D. Zelinsky Institute of Organic Chemistry RAS, Moscow, Russiagaidai@server.ioc.ac.ruThe reaction of methanation is used to remove CO from feeding gases in manyindustrial processes, such as, coal gasification, ammonia synthesis and hydrogenproduction. Although there are many publications on CO methanation over nickelcatalysts, there is no single opinion on kinetics and mechanism of this reaction. Maindistinctions of presented works on kinetics of CO methanation consist in the nature ofintermediate compounds (different oxygen compounds of CO or carbon formed atCO dissociation) taking part in the slow step of the process. In previous studies [1, 2]we have found some optimal compositions of catalysts with NiO supported over TiO 2 ,Al 2 O 3 , SiO 2 as well as γ-Al 2 O 3 + SiO 2 (mechanical mixture) for the CO methanation.They are the following: 7.5(wt.%)NiO/TiO 2 , 38NiO/Al 2 O 3 , 30NiO/SiO 2 and25NiO/30%γ-Al 2 O 3 +70%SiO 2 , of which two samples 7.5NiO/TiO 2 and 38NiO/Al 2 O 3have the most activity. Kinetics of the CO methanation over two catalysts has beenpresented in this work. The industrial application of nickel-alumina catalysts can bemore preferable than nickel-titania ones. Catalysts were prepared as described in [1].The catalysts were investigated by methods BET, XRD, TPR and hydrogen pulsetitration. Kinetic studies of the reaction were carried out in a gradientless circulatingreactor at atmospheric pressure; reaction temperatures were 180, 200, 220 and240 o C. The values of initial partial pressures of carbon monoxide (P o CO ), hydrogen(P o H2 ), water steam (P o H2O ) and methane (P o CH4 ) were changed in the ranges (atm):0.05-0.30; 0.17-0.67; 0-0.22 and 0-0.30, respectively. In these conditions the extentsof CO conversion were altered from 9% up to 95%. It was shown that the reactionproceeded in the kinetic region over catalyst particles less 1 mm.Surface characteristics of the catalysts are presented in Table. The values ofaverage pore size TiO 2 and Al 2 O 3 are respectively 28Å and 24Å, that easies thereactants and products to diffuse. The values of Ni crystals size in both the catalystsare approximately identical and suitable for this reaction (10 ÷ 20nm).268