# LiBr‐Formic Acid Enables Lignocellulosic Biomass Fractionation within 10  Minutes

## TL;DR

A new method using LiBr and formic acid quickly and efficiently separates biomass into high-purity components, aiding sustainable biofuel and material production.

## Contribution

A rapid, high-purity biomass fractionation method using LiBr-assisted formic acid is developed.

## Key findings

- The LB-FA system removed 96.0% of lignin and 99.6% of hemicellulose from poplar wood in 10 minutes.
- The cellulose obtained had 97.2% purity and retained the Iβ allomorph, with over 90% glucose yield after enzymatic hydrolysis.
- The lignin achieved 98.5% purity, demonstrating the system's effectiveness for sustainable material development.

## Abstract

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.

LiBr‐assisted formic acid fractionates lignocellulose in 10 min, removing 96.0% lignin and 99.6% hemicellulose to give high‐purity cellulose (97.2%, cellulose Iβ retained) and lignin (98.5%). The cellulose yields >90% glucose after 12 h of enzymatic hydrolysis.© 2025 WILEY‐VCH GmbH