Abstract
Co/SiO2, Mg-Co/SiO2, and Co-Mg/SiO2 catalysts were prepared from nitrate precursors to get more insight into the effect of magnesium promotion on the cobalt catalyst. The desorption characteristics and reactivity of the catalysts towards synthesis gas were evaluated in a pulse micro reactor connected to an on-line quadrupole mass spectrometer. The presence of MgO both decreased the extent of reduction and increased the dispersion of cobalt. The reactivity results suggested that MgO promotion created new types of active sites, probably at the edge sites of cobalt and magnesium. The highest activity per metallic site available was obtained with a Mg: Co molar ratio of 1/2, i.e. with a high amount of edge sites. In accordance with previous results the formation of CO2 was clearly suppressed in the presence of MgO, and methanol was formed in trace amounts.
Similar content being viewed by others
References
H. Schulz, Pure Appl. Chem. 51 (1979) 2225.
R.B. Anderson, W.K. Hall and L.J.E. Hofer, J. Am. Chem. Soc. 70 (1948) 2465.
J. Vaari, T. Vaara, J. Lahtinen and P. Hautojärvi, Appl. Surf. Sci. 81 (1994) 289.
J. Vaari, J. Lahtinen, A. Talo and P. Hautojärvi, Surf. Sci. 251/252 (1991) 1096.
J. Lahtinen, J. Vaari, A. Talo, A. Vehanen and P. Hautojärvi, Surf. Sci. 245 (1991) 244.
M.K. Niemelä, A.O.I. Krause, T. Vaara and J. Lahtinen, in:Fischer-Tropsch and Methanol Synthesis, Topics in Catalysis 2 (1995) 45.
M. Röper, in:Catalysis in C1 Chemistry, ed. W. Keim (Reidel, Dordrecht, 1983) ch. 2.
B.A. Sexton, A.E. Hughes and T.W. Turney, J. Catal. 97 (1986) 390.
P.G. Gopal, R.L. Schneider and K.L. Watters, J. Catal. 105 (1987) 366.
A.M. Efstathiou, J. Mol. Catal. 67 (1991) 229.
F. Solymosi, I. Tombácz and M. Kocsis, J. Catal. 75 (1982) 78.
A.M. Efstathiou, J. Mol. Catal. 69 (1991) 41.
K. Mohana Rao, G. Spoto and A. Zecchina, J. Catal. 113 (1988) 466.
M.P. Rosycalvinnek and C.A. Polansky, Appl. Catal. 73 (1991) 97.
C.H. Bartholomew, Catal. Lett. 7 (1990) 27.
A. Hoff, Dr. Tech. Dissertation, The University of Trondheim, Norway (1993).
R.C. Reuel and C.H. Bartholomew, J. Catal. 85 (1984) 63.
B. Viswanathan and R. Gopalakrishnan, J. Catal. 99 (1986) 342.
T.E. Holt, A.D. Logan, S. Chakraborti and A.K. Datye, Appl. Catal. 34 (1987) 199.
V. Ponec, Catal. Today 12 (1992) 227.
B.G. Johnson, C.H. Bartholomew and D.W. Goodman, J. Catal. 128 (1991) 231.
K. Takeuchi, T. Matsuzaki, T. Hanaoka, H. Arakawa and Y. Sugi, J. Mol. Catal. 55 (1989) 361.
R.C. Reuel and C.H. Bartholomew, J. Catal. 85 (1984) 78.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Niemelä, M.K., Krause, A.O.I. Characterization of magnesium promoted Co/SiO2 catalysts. Catal Lett 34, 75–84 (1995). https://doi.org/10.1007/BF00808324
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00808324