Conversion of Biomass to Liquid Fuels and Chemicals via the Fischer–Tropsch Synthesis Route
The chapter opens by examining how the Fischer-Tropsch synthesis (FT) reaction will likely take on an increasing role in the near-term for supplying high quality, high energy density transportation fuels, such as diesel and jet fuel, as well as chemicals; in the more distant future, FT products may serve as chemical carriers of hydrogen for mobile fuel cell applications. The flexibility of fuels produced from FT and upgrading lies in the fact that the syngas feed can be derived not only from natural gas and coal, but also from biomass and coal/biomass blends which aim to reduce carbon dioxide emissions. Considerations to be taken into account in converting biomass-derived syngas are then investigated, including the potential contaminants generated from the gasification of biomass that may poison downstream water-gas shift and FT catalysts, as well as the importance of capturing and sequestering or fixing carbon dioxide and sulfur. The general aspects of FT catalyst selection and reactor configuration are then discussed before moving to the specific issues of product tailoring, reaction kinetics, catalytic mechanisms, and the structure-function relationships of iron and cobalt FT catalysts.