Processing of lignocellulosic biomass derived monomers with high-pressure CO2 and CO2-H2O mixtures

Abstract

The degradation of monosaccharides, though often undesired in lignocellulosic pretreatment, often lead to the formation of products with a higher value than the same sugars. In this chapter, detailed information related to monomers-based lignocellulosic biomass decomposition towards value added products using both water alone and water/CO2 mixture is showed. We will analyse the reaction mechanisms leading to the rupture of the oligomers into monosaccharaides, and then they breakage through dehydration reactions or aldol reactions. It will be demonstrated that CO2 plays a determinant role in catalysis of hydrolytic reactions that take place in aqueous media. The optimum conditions for obtaining different products will be discussed, also providing some indications on which configuration to adopt, for increasing the selectivity of some reactions with respect to others.