Fe/MCM-41 SYLILATED CATALYST. STRUCTURAL CHANGES DETERMINATION.

J. F. BENGOA; N. A. FELLENZ; M.V. CAGNOLI,; L.A. CANO,; N.G. GALLEGOS,; A.M. ALVAREZ,; S.G. MARCHETTI

La Plata, Argentina

Conferencia; XI Latin American Conference on the applications of Mössbauer effects; 2008

Fischer-Tropsch synthesis (FTS) is a process used to produce a broad distribution of \clean" hydrocarbons from syngas using principally Fe catalysts [1]. Although it has been used industrially for decades, the main still unresolved problem is to reach a good selectivity toward desirable products. Two main approaches have been applied to this purpose: controlling the operative variables of the process (pressure, contact time, reactor selection or temperature) or modifying the structural properties of the catalysts. The last option is the more promising because the reaction is kinetically controlled. It is generally accepted that FTS is a structure-sensitive reaction [2]. A strategy to increase the selectivity is to obtain a catalyst with a narrow size distribution of active phase crystals which average size is within a determinate range. If a mesoporous solid like MCM-41 [3] would be used as iron support and if it would be possible to introduce the iron species mainly inside its channels, the small sizes of the obtained crystals would lead to highly selective catalysts towards the production of light hydrocarbons (HC), since the growth of chain would be limited