Hydrocarbon production rates in Fischer-Tropsch synthesis over a Fe/Cu/La/Si catalyst

The detailed kinetics of Fischer-Tropsch synthesis over an industrial Fe/Cu/La/Si catalyst was studied in a continuous spinning basket reactor under the conditions relevant to industrial operations. Reaction rate equations were derived on the basis of Langmuir-Hinshelwood-Hougen-Watson type models for Fischer-Tropsch synthesis based on possible reactions sets originated from the carbide, enolic and combined enol/carbide mechanisms. Kinetic model candidates were evaluated by the global optimization of kinetic parameters, which were realized by first minimization of multi-response objective functions with conventional Levenberg-Marquardt method. It was found that an enolic mechanism based model could produce a good fit of the experimental data. The activation energy for paraffin formation is 95 kJ·mol−1 which is smaller than that for olefin formation (121 kJ·mol−1).