New particle size-dependent kinetic model of the water-gas-shift reaction using an iron-based catalyst under Fischer-Tropsch conditions

The effect of nanoparticle size on the kinetics of the water-gas-shift (WGS) reaction using an iron based catalyst used in the Fischer-Tropsch synthesis (FTS) was studied in a continuous spinning basket reactor. A series of iron oxide particles with different particle sizes doped with copper and lanthanum was prepared as the catalyst. A new size-dependent kinetic model for the WGS reaction has been developed by a thermodynamic method. The kinetic parameters of the model were evaluated from experimental results for iron catalysts with different particle sizes. The results show that the parameters of the size-dependent model changed with temperature and particle size. The surface tension energy (sigma) of the iron oxide catalyst and the size-independent activation energy for the WGS reaction was calculated from the experimental results. The size-independent activation energy for the WGS reaction is calculated as 4 kJ mol(-1) based on haematite particles.