Chapter 6 - Integrated Bio- and Chemocatalytic Processing for Biorenewable Chemicals and Fuels

Abstract

Biomass as an alternative to fossil fuels has shown significant potential to produce fuels and chemicals. Analogous to a petrochemical refinery, a biorefinery can be envisaged, where a diverse variety of products will be synthesized. These products can be made either through biological or chemical catalytic routes. Technologies relying solely on biological or chemical conversion methods have shown limitations in achieving high yield of a desired product. As an alternative, an integrated processing strategy can be applied where an intermediate chemical (e.g. lactic acid) or platform molecule is produced through biological transformation, which can be upgraded into useful compounds (e.g. propylene glycol) by chemical catalysis. This study is focused on such integrated methods, which have been applied to produce commodity chemicals and fuels. For the development of an integrated process, heterogeneous catalysts are required, which may be deactivated by the interaction of biogenic impurities, present in the fermentation media. A detailed overview of the available knowledge is presented on the mechanism leading to the deactivation of the catalyst surface by biogenic impurities, which will aid in the better design of the catalyst and purification process. In this regard, electrodialytic purification of the fermentation media is explored as an option for providing economic extraction of the product suited for subsequent catalytic processing. While studies on biogenic impurities are limited only to the hydrogenation reaction on metal surfaces, similar understandings can be applied to other catalytic reactions. Fundamental concepts introduced in this chapter can thus be applied for the development of an integrated process for the conversion of biomass-derived novel platform molecules into high-value chemicals and fuels.