Solvente Eutético Profundo à Base de Cloreto de Colina para Deslignificação do Bagaço de Cana-deAçúcar

Resumo

Lignocellulosic ethanol (or second-generation ethanol) presents a viable alternative to fossil fuels,
addressing global energy demands. However, the removal of lignin from biomass (raw material) before
bioconversion remains a significant challenge in this biorefinery process. Deep eutectic solvents (DESs)
offer a promising solution for the pretreatment of such renewable sources. This work aims to evaluate
and optimize the use of choline chloride-urea DESs (ChU) for the steam-pressurized delignification of
sugarcane bagasse. Preliminary investigations showed that ChU yielded the most promising results among
the various agents tested. To optimize delignification, an experimental design was employed, focusing on
three independent variables: the volume of extractant solvent, water addition to the DESs, and extraction
time. Under optimized conditions, a significant reduction in the lignin content of the final material was
achieved (58.38%). Such conditions comprised a 1:10 biomass-solvent ratio, water addition of 6% (w w^-1)
to the ChU solvent, and an extraction time of 2 hours at 120 ºC. The results of this study are noteworthy
both economically and environmentally, particularly when compared to recent studies in the biorefinery
field, offering new perspectives for future research.