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Updated: Dec 20, 2025
10:18
Extraction of Lignin with High β-O-4 Content by Mild Ethanol Extraction and Its Effect on the Depolymerization Yield
Published on: January 7, 2019
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Heteroatom-participated lignin cleavage to functionalized aromatics
Hongji Li1, Anon Bunrit2, Ning Li2
1State Key Laboratory of Catalysis (SKLC), Dalian National Laboratory for Clean Energy (DNL), Dalian Institute of Chemical Physics (DICP), Dalian 116023, China. wangfeng@dicp.ac.cn and University of Chinese Academy of Sciences, Beijing 100049, China.
Chemical Society Reviews
|May 28, 2020
Summary
Heteroatoms like nitrogen, silicon, iodine, and lithium can cleave bonds in lignin, a natural polymer. This process yields valuable functionalized aromatic compounds for diverse applications, advancing biorefinery technologies.
Area of Science:
- Biomass Conversion and Biorefining
- Organic Chemistry
- Sustainable Chemistry
Background:
- Lignin, a major aromatic biopolymer, is a key resource for sustainable fuels and chemicals.
- Current lignin depolymerization primarily yields hydrocarbons and oxygenates, limiting the scope of derived products.
- The biorefinery concept requires a wider array of fine chemicals, including heteroatom-containing compounds.
Purpose of the Study:
- To review recent advancements in lignin C-C and C-O bond cleavage reactions induced by heteroatoms (N, Si, I, Li).
- To explore the generation of functionalized aromatic products containing C-X and O-X bonds from lignin.
- To discuss the potential applications of these novel lignin-derived compounds.
Main Methods:
- Summarizing representative reaction pathways for lignin depolymerization using heteroatom-induced cleavage.
- Evaluating the feasibility of these methods using lignin models and extracts.
- Compiling information on the synthesis and applications of heteroatom-functionalized lignin monomers.
Main Results:
- Heteroatom-induced reactions effectively cleave C-C and C-O bonds in lignin.
- Functionalized aromatic monomers containing C-N, C-Si, C-I, and C-Li bonds are produced.
- These methods offer pathways to diverse lignin-derived chemicals beyond traditional hydrocarbons and oxygenates.
Conclusions:
- Heteroatom-mediated lignin depolymerization is a promising strategy for accessing value-added chemicals.
- The resulting functionalized monomers have broad potential in synthetic chemistry, pharmaceuticals, dyes, and energy storage.
- This approach significantly expands the utility of lignin in future biorefineries.
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