The effect of particle size on the activity of a fused iron catalyst used for the Fischer-Tropsch synthesis has been studied. The significant resistance in our tests was found to be intraparticle mass transfer, which was caused by the low diffusivity of reactant in wax-filled catalyst pores. Particles of 30/60 and 60/100 mesh show strong mass-transport limitations with lower than expected activities and activation energies, while catalyst activity approaches its intrinsic value for 170/230-mesh particles. Catalyst effectiveness factors were calculated assuming first-order reaction kinetics and single reaction stoichiometry and were compared to those obtained by experiment. The calculated and experimental results were in good agreement, although the calculated values were consistently higher than the experimental values. The overprediction may be caused by basing the Thiele modulus on the diffusivity of H2 or by neglecting rate inhibition by water.
|Number of pages||8|
|Journal||Industrial and Engineering Chemistry Research®|
|Publication status||Published - 1989|
ASJC Scopus subject areas
- Chemical Engineering (miscellaneous)
- Environmental Science(all)
- Polymers and Plastics