III International Conference

PP-II-51hydrogenation. This peculiarity reveals itself in extremely high selectivity of the Fischer-Tropsch process with respect to olefins (see Figures 1 and 2). Anomalous symbatetemperature dependence of selectivity to olefins is also worth to mention.Figure 2. The experimental olefin contents in the condensed Fischer-Tropsch products;catalyst catalyst CoFe/Al 2 O 3 ; P = 1 bar, T = 210 o C; H 2 :CO:N 2 = 6:3:1; CO conversion extent15-20 %.Increasing the process pressure to 10-20 bar leads to dramatic change in catalyticproperties of the studied CoFe catalysts. Among the most important changes is dramaticdiminishing the selectivity to olefins and the rate of the secondary WGSR process. Theplausible explanation of the observed pressure effect on the catalytic properties of the studiedCoFe catalysts is the impact of the reaction mixture to the structure and physico-chemicalproperties of the surface of the active component particles.The research was financially supported by the Ministry of Science and Education of RF,contract # 11.434.11.2004.257