Chapter 9 – Conversion of Biomass to Chemicals: The Catalytic Role of Zeolites

Since the mid-20th century zeolites have been successfully applied in oil refining and petrochemistry, owing to the strong Bronsted acidity of their protonated form in a porous crystalline matrix. Yet, concerns about the excessive use of fossil fuels force researchers to develop processes for the production of fuels and chemicals from CO2-neutral feedstocks such as biomass, considered as the alternative and sustainable source of carbon for the production of future bio-derived chemicals. With their success in refinery and petrochemistry, there is increasing interest in the use of zeolites in biomass processing, and this has already resulted in the gradual entrance of zeolites in the conversion of biomass feedstocks. Many interesting biomass conversions have been demonstrated today using the unique acid and redox chemistry of zeolites. However, there are disadvantages inherent to the biomass conversion that need to be overcome before zeolite chemistry can play as important a role in the conversion of biomass as in the conversion of fossil feedstocks. These disadvantages include unstable products and complex conversion network schemes, the stability of zeolites in often polar (condensed) media and active site accessibility of large biomolecules. This chapter presents the major organic compounds in biomass feedstock and provides an overview of the numerous chemical reactions with these chemicals using zeolites in the bulk and fine chemistry. Developments and future challenges in the area are summarized.