The influence of the cobalt particle size in determining Fischer-Tropsch synthesis (FTS) performance for carbon nanotubes (CNT) supported catalysts was investigated. The catalysts prepared by two different methods (microemulsion and impregnation) and to achieve a series of catalysts with different Co particle size, water-to-surfactant molar ratio (W/S) in microemulsion system varied from 2 to 12 in microemulsion system. To understand the effect of particle size on the cobalt catalytic activity, kinetic studies were performed using a useful equation. The size dependent kinetic parameters were developed by thermodynamic method to evaluate of structural sensitivity of cobalt supported on CNT catalysts. The results show that both size independent FTS reaction rate constant (k∞) and size independent adsorption parameter (b∞), increased by increasing the reaction temperature. In addition, the Polani parameter of χ is a size dependent parameter due to changes in coverage of catalyst surface.

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