Bridging the pressure and material gap in heterogeneous catalysis: cobalt Fischer-Tropsch catalysts from surface science to industrial application.

Abstract

The Fischer-Tropsch (FT) process is the heart of many natural gas conversion processes as it enables the conversion of a mixture of CO and H(2) into valuable long-chain hydrocarbons. Here we report on the use of state-of-the-art surface science techniques to obtain information on the relationship between the surface atomic structure of model catalysts and their performance in the Fischer-Tropsch reaction. Cobalt single crystals and polycrystals were modified with non-reducible oxides as to resemble industrial catalysts. Reflection absorption infrared spectroscopy was used for examining the CO adsorption behaviour at room temperature as well as at 493 K at CO pressures spanning 10(-7) to 300 mbar on both (modified) Co single/polycrystals and an industrial catalyst. Polarization modulation was applied to cancel the CO gas phase absorption. Subsequently, they were subjected to reaction tests in the same apparatus at 1 bar and 493 K. This allowed us to close the material, pressure and instrument gap in the field of Fischer-Tropsch synthesis on cobalt-based catalysts.