Fundamentals of Biomass Pretreatment by Fractionation

This chapter focuses on organosolv pretreatment as a method for biomass fractionation to recover high-quality streams of each of the major biomass components. It provides a short historical perspective on organosolv pulping and pretreatment. Different solvents and catalysts used in organosolv pretreatment and results from biomass fractionation are discussed with an emphasis on ethanol, as it is an excellent solvent when the production of bio-ethanol is desired. The chemistry of organosolv delignification, a key component of biomass fractionation by this method, and the nature of organosolv lignin are described. The chapter also discusses other aspects, including modifications in the structure and crystallinity of cellulose after organosolv pretreatment and the co-products of biomass fractionation by ethanol organosolv pretreatment.