Kinetics of the Fischer-Tropsch Reaction over a Ru-Promoted Co/Al2O3 Catalyst

The kinetics of the Fischer Tropsch (FT) synthesis reaction over 0.27 % Ru 25 % Co/Al2O3 catalyst was studied in a IL stirred tank slurry reactor (STSR). Experiments were conducted at reactor pressures of 1.4 MPa and 2.4 MPa, temperatures of 205 degrees C and 220 degrees C, H-2/CO feed ratios of 1.4 and 2.1 and gas space velocities ranging from 2 to 15 NL/g-cat-h. Langmuir-Hinshelwood-Hougen-Watson (LHHW) type rate equations were derived on the basis of a set of reactions originating from carbide and enolic pathways for hydrocarbon formation. Derived rate equations were fitted to the corrected experimental rate using Levenberg-Marquardt method to obtain model parameters. Physical and statistical tests were used to discriminate between rival models. It was found that a model based on hydrogen-assisted dissociative adsorption of CO followed by hydrogenation of dissociatively adsorbed CO provides the best fit to the data.