In-situ spectroscopic investigations of Fischer-Tropsch catalysts

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ObjectivesThis project aims to gain new insight into the mechanisms of operation of Manganese-promoted cobalt oxide catalysts for the Fischer-Tropsch (FT) reaction by using Near-Ambient Pressure X-Ray Photoelectron Spectroscopy (NAP-XPS surface sensitive spectroscopic technique) to study the surface chemistry of the catalyst in-situ. In particular, manganese doping has been shown to be benefical to the catalyst's activity and selectivity, but it is not well understood whyThe objectives are:Develop methodology to be able to study real commercial FT catalysts using Near-Ambient Pressure XPSInvestigate the effect of manganese doping on the reduction of the catalystInvestigate the evolution of the surface chemistry of the reduced catalyst in response to water exposurePerform the Fischer-Tropsch reaction in-situ in NAP-XPS to elucidate the nature of the active phaseApproachThe student will employ NAP-XPS to study catalyst samples supplied by BP. To complement our understanding of these materials, the student may also develop simpler model catalysts based on foils and/or evaporated thin films. Other complementary characterization may include but not be limited to: catalytic testing, Infrared Spectroscopy and Raman SpectroscopyNovel science contentTechnique development Mechanistic understanding of heterogeneous catalysts in general lags far behind materials discovery, meaning that most catalysts are discovered by trial-and-error. By studying the surface chemistry of catalysts in-situ, we can gain fundamental understanding of how they work which will allow the rational design of new catalysts. Developing NAP-XPS methodology to study catalysts in-situ is a vital component of this and could be broadly applicable to diverse catalytic systemsUnderstanding the Fischer-Tropsch processThe FT process converts a feedstock of carbon monoxide and hydrogen into synthetic fossil fuels (gasoline, diesel and kerosene). It is an attractive proposition in light of the need to reduce carbon emissions as the feedstock can come from renewable sources such as biomass or municipal solid waste - potentially enabling "green" fossil fuels. Improving the selectivity, stability and activity of FT catalysts via understanding in detail how they work could hold the key to the widespread adoption of FT as a technology.