Liquid systems for the valorisation of lignocellulosic biopolymers

Resumo

Lignocellulosic biomass is a key biorenewable source in the transition of the current industrial platform for the production of chemicals and materials to a more sustainable scheme. It is presently accepted that the viable exploitation of this type of biomass should include an integral valorisation of its major constituent biopolymers. The work of this thesis focuses on the two main ones: cellulose and lignin. In a first part, the pretreatment of cellulose with liquid formulations based on ionic liquids was studied, with the purpose of improving its reactivity. Better reaction rates were observed both in the enzyme hydrolysis and in the carboxymethylation of the pretreated samples. In a second part, the depolymerisation of lignin via aqueous solutions of an ionic liquid or alternative aqueous systems was explored. Although in limited yields, a number of value-added phenolic compounds were identified after the treatments.