Kinetics study of CO hydrogenation on a precipitated iron catalyst

The kinetics of the gas–solid Fischer–Tropsch synthesis over a precipitated Fe/Cu/La/SiO2 catalyst was studied in a well mixed, continuous spinning basket reactor. A wide range of synthesis gas conversions have been obtained by varying experimental conditions. Several Langmuir–Hinshelwood–Hougen–Watson type rate equations were derived based on detailed sets of possible reaction mechanisms originating from the carbide, enolic and combined enol/carbide mechanisms. Three models for the Fischer–Tropsch reaction rate were fitted to the experimental reaction rates. Kinetic parameters of models are determined using the genetic algorithm approach (GA), followed by the Levenberg–Marquardt (LM) method to make refined optimization, and are validated by means of statistical analysis. Simulations using the optimal kinetic models derived showed good agreement with experimental data.