FISCHER-TROPSCH SYNTHESIS OVER COBALT-CONTAINING UNSUPPORTED CATALYSTS IN SLURRY REACTOR - EFFECT OF THE METALLIC CO PARTICLE-SIZE ON THE CATALYST SELECTIVITY

Catalytic properties of a variety of Co-MgO and Co-ZnO unsupported cat alysts were investigated in Fischer-Tropsch synthesis in a tetradecane -filled slurry reactor at atmospheric pressure and a CO/H-2 ratio 1:2. An effect of size of dispersed metallic cobalt on the selectivity of catalyst in the FT synthesis (the a value of the Anderson-Schulz-Flory distribution) has been found: the smaller the particle, the higher th e a value. A possibility to control the a value in the range of 0.6-0. 8 for both saturated and unsaturated hydrocarbons has been shown. An e xplanation of the above data can be based on an assumption that hydrog en atoms dissolved in octahedral interstitial positions of the metalli c cobalt particle lattice are responsible for hydrogenation of the FT hydrocarbon intermediates into the hydrocarbons.