Oxidative Bagasse Fractionation for Its Efficient Utilization Based on a Lignin-First Approach

Area of Science:

• Biomass Refining
• Green Chemistry
• Materials Science

Background:

• Biological refining faces challenges with harsh chemicals and high temperatures.
• Efficient separation of lignin and carbohydrates is crucial for biomass valorization.
• Existing lignin extraction methods often result in low yields and poor quality.

Purpose of the Study:

• To develop a one-pot method for extracting and separating lignin and carbohydrates from biomass.
• To investigate the potential of aerobic oxidation in biomass pretreatment.
• To enhance the depolymerization performance of extracted lignin.

Main Methods:

• Combined biomass hydrolytic fractionation and in situ lignin oxidative modification.
• Optimized aerobic oxidation pretreatment conditions.
• Analysis of oxidized lignin structure and depolymerization products.
• Characterization of carbon materials derived from carbohydrate residue.

Main Results:

• Achieved yields of 17.1% for oxidized lignin and 59.9% for carbohydrate residue.
• Oxidized lignin yielded ~245.0 mg g^-1 phenolic monomers, significantly higher than Kraft lignin and sodium lignosulfonate.
• Identified aryl α-ketone functional groups in oxidized lignin as key to enhanced depolymerization.
• Developed graphene-like carbon materials with hierarchical porous structures from carbohydrate residue.

Conclusions:

• Aerobic oxidation offers a sustainable pretreatment for efficient biomass refining.
• The lignin-first approach enables simultaneous valorization of both lignin and carbohydrate components.
• This method presents a promising pathway for comprehensive biomass utilization.