Preparation and Characterization of CoMn/TiO2 Catalysts for Production of Light Olefins

Document Type : Research Article


Department of Chemistry, Faculty of Sciences, University of Sisstan and Baluchestan, P.O. Box 98135-674 Zahedan, I.R. IRAN


A series of x(Co, Mn)/TiO2 catalysts (x=2–12wt.%) containing 25%Co and 75%Mn were prepared by the co-impregnation method. All prepared catalysts have been tested in Fischer-Tropsch synthesis for production of C2-C4 olefins. It was found that the catalyst containing 8wt.%(Co,Mn)/TiO2 is an optimal catalyst for production of C2-C4 olefins. The effect of operation conditions such as the H2/CO molar feed ratios, temperature, Gas Hourly Space Velocity (GHSV) and total reaction pressure on the catalytic performance of optimal catalyst was investigated. Characterizations of both precursors and catalysts were carried out using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Brunauer-Emmett-Teller (BET) specific surface area measurement, Thermal Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC).


Main Subjects

1] Sergio  L.,  Gobzalez-Cortes  S.L.,  Serbia M., Rudolfo-Baecher A., Oliveros A., Oeozco J., Fontal B., Mora A.J., Delgado G., Synthesis and Structure of Bimetallic Nickel Molybdenum Phosphide Solid Solutions, Reac. Kinet. Catal. Lett., 75, p. 3 (2002).
[2] Tihay F., Pourroy G., Richard-Plouet M., Roger A.C., Kiennemann A., Effect of Fischer-Tropsch Synthesis on the Microstructure of Fe-Co Based Metal/Spinel Composite Materials, Appl. Catal. A: Gen., 206, p. 29 (2001).
[3] Tihay F., Roger A.C., Kiennemann A., Pourroy G., Fe-Co Based Metal/Spinel to Produce Light Olefins from Syngas, Catal. Today., 8, p. 263 (20005).
[4] Yang C.H., Massoth F.E., Oblad A.G., Kinetics of Carbon Monoxide and Hydrogen Reaction Over Cobalt-Copper-Alumina Oxide Catalyst, Adv. Chem. Ser., 78, p. 35 (1979).
[5] Rautavoma A.O., Van der Baan H.S., Effects of Support and Dispersion on the CO Hydrogenation Activity/Selectivity Properties of Cobalt, Appl. A: Gen., 1, p. 247 (1981).
[6] Tavasoli A., Irani M., Nakhaeipour A., Mortazavi Y, Khodadadi A.A., Ajay K.D., Preparation of a Novel Super Active Fischer-Tropsch Cobalt Catalyst Supported on Carbon Nanotubes, Iran. J. Chem. Chem. Eng., 28, 37 (2009).
[7] Chanenchuk C.A., Yates I.C., Satterfield C.N., The Fischer-Tropsch Synthesis With a Mechanical Mixture of a Cobalt Catalyst and a Copper-Based Water Gas Shift Catalyst, Energy Fuels., 5, 847 (1991).
[8] Hayakawa H., Tanaka H., Fujimoto K., Studies on Catalytic Performance of Precipitated Iron/Silica Catalysts for Fischer-Tropsch Synthesis, Appl. Catal. A: Gen., 328, p. 17 (2007).
[9] Tauster S.J., Fung S.C., Garden R., Strong Metal-Support Interactions Group 8 Noble Metals Supported on Tio2, J. Am. Chem. Soc., 100, p. 170 (1978).
[10] Ma X.D., Sun Q.W., Cao F.H., Ying W.Y., Fang D.Y., Effects of the Ratio of Fe to Co Over Fe-Co/SiO2 Bimetallic Catalysts on Their Catalytic Performance for Fischer-Tropsch Synthesis, J. Natur. Gas. Chem.,
(4), p. 335 (2006).
[11] Copperwaite R.G., Hutchings G.J., Van der Riet M., Woodhouse J.R., Carbon Monoxide Hydrogenation Using Manganese Oxide-based Catalysts: Effect of Operating Conditions on Alkene Selectivity, Int. Eng. Chem. Res., 26 (2), p. 969 (1987).
[12] Bussemeier B., Frohning C.D., Cornils B., Effects of Iron Manganese Oxide Solid Solutions on Selectivity for Lower Hydrocarbons From Carbon Monoxide Hydrogenation, Hydrocarb. Process., 55 (11), p. 105 (1976).
[13] Van den Berg F.R., Craje M.W.J, Van der Kraan A.M., Geus J.W., Reduction Behaviour of Fe/ZrO2 and Fe/K/ZrO2 Fischer-Tropsch Catalysts, Appl Catal A: Gen., 242 (2), p. 403 (2003).
[14] Wu B.S., Tian L., Xiang H.W., Zhang Z.X., Li Y.W., Novel Precipitated Iron Fischer-Tropsch Catalysts with Fe3O4 Coexisting with a-Fe2O3, Catal Lett, 102 (3-4), p. 211 (2005).
[15] Colley S., Copperthwaite R.G., Hutchings G.J., Van der Riet M., Carbon Monoxide Hydrogenation Using Cobalt Manganese Oxide Catalysts, Ind. Eng. Chem. Res., 27, p. 1339 (1988).
[16] Van der Riet M., Hutchings G. J., Copperthwaite, R.G., Low Methane Selectivity Using Co/MnO Catalysts for the Fischer-Tropsch Reaction: Effect of Increasing Pressure and Co-Feeding Ethene, J. Chem. Soc. Chem. Commun., 98 (6), p. 798 (1986).
[17] Van der Riet M., Hutchings G.J., Copperthwaite R.G., Carbon Monoxide Hydrogenation Using Cobalt-Manganese Oxide Catalysts: The Influence of Potassium as a Promoter, J. Chem. Soc. Faraday Trans., 1 (83),p. 2963 (1987).
[18] Dry M. E., The Fischer-Tropsch Process: 1950-2000, Catal. Today., 71, p. 227 (2002).
[19] Iglesia E., Soled S.L., Fiato R.A., Fischer-Tropsch Synthesis on Cobalt and Ruthenium. Metal Dispersion and Support Effects on Reaction Rate and Selectivity, J. Catal., 137, p. 212 (1992).
[20] Shayegh F., Ghotbi C., Bozorgmehri R., Manafi H., Mirzaei A.A., Feyzi M., Optimum Operating Conditions of Recently Developed Co/Mn/TiO2 Catalyst for Conversion of Synthesis Gas to Light Olefins, submitted in Appl. Catal. A: Gen (2010).
[21] Shroff M.D., Kalakkad D.S., Coulter K.E., Kohler S.D., Harrington M.S., Jackson N.B., Sault A.G., Datye A.K., Activation Pressure Studies with an Iron-based Catalyst for Slurry Fischer-Tropsch Synthesis, J. Catal., 156, p. 185 (1995).
[22] Zhang H.B., Schrader G.L., Characterization of a Fused Iron Catalyst for Fischer-Tropsch Synthesis by in Situ Laser Raman Spectroscopy, J. Catal.,, 95 (3), p. 325 (1985).
[23] Barrault J., Forquy C., Perrichon V., Effects of Manganese Oxide and Sulphate on Olefin Selectivity of Iron Supported Catalysts in the Fischer-Tropsch Reaction, Appl. Catal. A: Gen., 5, p. 119 (1983).
[24] Griboval-Constant A., Khodakov A.Y., Bechara R., Zholobenko V.L., Support Mesoporosity: a Tool for Better Control of Catalytic Behavior of Cobalt Supported Fischer Tropsch Catalysts, Stud. Surf. Sci. Catal,. 144, p. 609 (2002).