Effect of Crystallite Size Distribution on the Oxidation and Re-reduction of Cobalt in the Fischer–Tropsch Synthesis: A Thermodynamic Analysis

Abstract

Nano-sized cobalt crystallites may oxidize under realistic Fischer–Tropsch conditions, especially when operating at high conversion where oxygen availability on the surface is large. The extent of deactivation due to oxidation differs for monodispersed catalysts as opposed to a log-normal distribution of cobalt crystallites. The optimum cobalt crystallite size for a Fischer–Tropsch catalyst is dependent on not only the mean particle size, but also the log-normal variance and conversion level.