Lignin: isolation, structure and valorisation

Lignin is the second most abundant polymer in forest biomass after cellulose. Compared to the ubiquitous use of cellulose, lignin is currently simply being wasted. In fact, as a waste product in the cellulose production, it serves mainly for the generation of energy. The reason for this lies in the challenging structural features and the patchy understanding of the correlation between structural features and polymer characteristics displayed by various lignins. This chapter will introduce the general characteristics and peculiarities of lignin as biopolymer and will present techniques for investigating structural issues. Approaches toward a valorization of lignin will be highlighted, showing the possibilities for using lignin in chemistry and material sciences.