Water-gas-shift kinetics over a Fe/Cu/La/Si catalyst in Fischer–Tropsch synthesis

The kinetic modeling of the water-gas-shift (WGS) reaction over a Fe/Cu/La/Si catalyst under Fischer–Tropsch synthesis (FTS) reaction condition was investigated. A number of Langmuir–Hinshelwood–Hougen–Watson type rate expression based on possible reaction sets, originated from the formate and direct oxidation mechanisms, were derived. Four models were used to fit the experimental data over a wide range of reaction condition. WGS rate expressions based on the formate mechanism were found to provide an improved description for WGS kinetic data. Experimental kinetics results showed that the WGS reaction under FTS reaction conditions was far from equilibrium.