Solange I. Mussatto
Head of Research Group (Biomass Conversion and Bioprocess Technology), Technical University of Denmark, Novo Nordisk Foundation Center for Biosustainability (email@example.com).
The desire for a more sustainable future, with lower emissions of carbon and sulfur to the atmosphere, a more appropriate reuse and valorization of wastes, and less dependency on oil has motivated the society to develop processes based on the use of renewable biomass as a feedstock for the production of fuels, chemicals, energy and materials. In fact, biomass can be used to replace fossil feedstock for the production of different products and this creates abundant growth opportunities for the industrial sector and the global economy. In addition, a bioeconomy has also potential to generate new jobs and new opportunities for entrepreneurship, with further benefits to the society. In view of this, great efforts have been made to develop processes that use biomass as raw material for the production of fuels and chemicals, capable of being implemented on an industrial scale. In the recent years, important advances have been observed in this area and some bioprocesses are already available in a large scale. However, there are still significant technological challenges to overcome in order to develop more efficient, sustainable and robust bioprocesses, able to compete with the optimized petrochemical production chains currently available.
The recovery and conversion of hemicellulose sugars to different products, for example, is a topic that still requires great attention. Lignocellulosic biomass usually contains 25-40% hemicellulose, a fraction whose key building block is the pentose sugar xylose. Unfortunately, xylose cannot be efficiently utilized by many microorganisms and, for the development of a bioeconomy, the conversion of xylose into industrially relevant products is of great importance. In addition, xylose is usually recovered from biomass in a liquid medium containing a mixture of several components, including compounds toxic to microorganisms. The generation of toxic compounds is unavoidable during the biomass fractionation step, and such compounds inhibit the metabolism of the microorganisms during fermentation. Although many efforts have been done to reduce the toxicity of biomass hydrolysates, this topic still deserves attention.
Hemicellulose sugars are released during the biomass pretreatment step. Although different technologies have been proposed for biomass pretreatment/fractionation, this step is still responsible for the main costs in the overall conversion/production chain. Therefore, the development of efficient and low-cost pretreatment technologies has been strongly encouraged. Finally, the development of highly efficient fermentation processes able to result in high product yield and productivity, and an appropriate recovery and valorization of the lignin fraction are also areas with huge potential to be explored in order to accelerate the bioeconomy. All these aspects will be presented and discussed in this presentation.
Acknowledgments: The Novo Nordisk Foundation (Denmark), NNF Grant number: NNF10CC1016517.