LiBr‐Formic Acid Enables Lignocellulosic Biomass Fractionation within 10  Minutes

Efficient biomass fractionation is essential for enhancing resource efficiency in the circular bioeconomy. However, achieving rapid, effective fractionation while minimizing the use of non-recyclable chemicals remains challenging and also often yields low component purity. To circumvent these issues, an LiBr-assisted formic acid (LB-FA) system is developed that enables biomass fractionation within 10 min without auxiliary technologies. It is found that adding LiBr facilitates biomass swelling, improving liquid penetration and component-removal efficiency. Moreover, LiBr promotes the dissociation of formic acid, enhancing the removal of hemicellulose and lignin. The LB-FA system removed 96.0% of lignin and 99.6% of hemicellulose from poplar wood, yielding cellulose with 97.2% purity and lignin with 98.5% purity. The cellulose retained Iβ allomorphs, and enzymatic hydrolysis achieved over 90% glucose yield in 12 h. This strategy provides a rapid, sustainable route for producing high-purity biomass components, facilitating bioethanol production and other sustainable material development applications.