C.J. Weststrate

Fischer-Tropsch synthesis : catalysts and chemistry

The Fischer–Tropsch synthesis represents a time-tested and fully proven technology for the conversion of synthesis gas (COxa0+xa0H 2 ) into paraffins, olefins, and oxygenated hydrocarbons. Depending on the origin of the syngas, one speaks of gas-to-liquids, coal-to-liquids, biomass-to-liquids, or ‘anything’-to-liquids. Industrial Fischer–Tropsch plants run on iron or cobalt catalysts, in fixed-bed-, fluidized-bed-, or slurry bubble-column-type reactors. The Fischer–Tropsch synthesis has inspired a wealth of academic and industrial research, and questions as to the mechanism of the process, how to control the selectivity of the polymerization process, the surface structure of the active catalysts, and the reasons why the catalysts deactivate continue to be subjects of intense discussion at conferences and in the literature. This chapter presents an overview of the Fischer–Tropsch synthesis, its historical development, the different modes of operation, the reactor technology, the synthesis and characteristics of the catalysts, and the mechanism of the reactions.

Studying Fischer–Tropsch catalysts using transmission electron microscopy and model systems of nanoparticles on planar supports

Nanoparticle model systems on planar supports form a versatile platform for studying morphological and compositional changes of catalysts due to exposure to realistic reaction conditions. We review examples from our work on iron and cobalt catalysts, which can undergo significant rearrangement in the reactive environment of the Fischer–Tropsch synthesis. The use of specially designed, silicon based supports with thin film SiO2 enables the application of transmission electron microscopy, which has furnished important insight into e.g. the mechanisms of catalyst regeneration.