Efficient hydrolysis of cellulosic biomass to glucose is a grand challenge for the realization of a nonfood biorefinery. In recent years, solid catalysts have attracted significant attention for biomass conversion, as they can be separated from product solutions and their functions can be designed. In this chapter, we describe activated carbons that can hydrolyze cellulose and real biomass to glucose in yields up to 88 % in the presence of a trace amount of hydrochloric acid. Creating contacts between the solid catalyst and the solid substrate by ball-milling is the key to realizing the potential of this catalytic system. Activated carbon adsorbs cellulosic molecules by van der Waals forces, CH-Π hydrogen bonds, and hydrophobic interactions between the polyaromatic surface of the carbon and the axial planes of glucans, namely, hydrophobic groups. Subsequently, the weakly acidic groups of the carbon surface such as carboxylic acids cleave the glycosidic bonds of cellulose via oxocarbenium intermediates, for which the salicylic acid structure is especially effective.
|Title of host publication
|Reaction Pathways and Mechanisms in Thermocatalytic Biomass Conversion I
|Subtitle of host publication
|Cellulose Structure, Depolymerization and Conversion by Heterogeneous Catalysts
|Number of pages
|Published - 2015 Sept 25
- Activated carbon