In this thesis the use of foamed iron (III) oxide catalysts for the production of liquid fuels from a carbon dioxide rich bio syngas via the Fischer Tropsch process is evaluated. Unsupported Fe2O3 catalysts promoted with Cu and K are generated using both a co precipitation and a foaming sol gel process before being characterised to study the effect of synthesis conditions on physical properties. Experiments were then performed in a purpose-built fixed bed reactor to assess the catalyst performance under industrial Fischer Tropsch conditions. The co precipitated catalysts, both unpromoted and promoted, were shown to have activity in the Fisher Tropsch reaction. Promotion increased the rate of conversion of syngas to hydrocarbons and increased production of longer chain lengths.
In contrast, the unpromoted foamed catalysts exhibited little Fischer Tropsch activity. However, high levels of inherent activity are achieved once promoted. All the promoted foamed catalysts produced a comparable product range, with similar Anderson Schulz Flory distributions being seen. However overall rates of conversion CO and H2 to hydrocarbons varied within the promoted foamed catalyst group. Higher calcination temperatures resulted in a dramatic loss of microporous surface area and hence lower overall hydrocarbon production rates as active surface sites were lost. Production rates over foamed catalyst pellets in excess of 300μm diameter suffered from the introduction of mass transfer limitations, thus reducing the rate.
In addition, a new dynamic model of the Fischer Tropsch reaction was developed, accounting for variable temperature dependant gas density and the reduction in gas velocity as the reaction proceeds. This was used to investigate the dynamic thermal response of the reactor to changes in inlet conditions, demonstrating the exaggeration of thermal responses generated when reaction contraction is accounted for. The phenomenon of wrong way behaviour over a fixed bed is also reviewed for loss of feed heating and reduced feed flow cases.