Depolymerization of lignin over heterogeneous Co-NC catalyst

Fei Song; Kai Du; Huamei Yang; Qi Luo; Yuxuan Liu; Qian Qiang; Yangming Ding; Qingda An; Changzhi Li

doi:10.1016/j.jes.2024.05.025

Depolymerization of lignin over heterogeneous Co-NC catalyst

J Environ Sci (China). 2025 Jun:152:654-663. doi: 10.1016/j.jes.2024.05.025. Epub 2024 May 24.

Authors

Fei Song¹, Kai Du², Huamei Yang³, Qi Luo¹, Yuxuan Liu⁴, Qian Qiang⁵, Yangming Ding³, Qingda An⁶, Changzhi Li⁷

Affiliations

¹ Liaoning Key Lab of Lignocellulose Chemistry and BioMaterials, Liaoning Collaborative Innovation Center for Lignocellulosic Biorefinery, School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China; CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
² Yulin Key Laboratory of Resource Utilization of Coal Chemical Waste, Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization, School of Chemistry and Chemical Engineering, Yulin University, Yulin, 719000, China.
³ CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
⁴ CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China; Yulin Key Laboratory of Resource Utilization of Coal Chemical Waste, Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization, School of Chemistry and Chemical Engineering, Yulin University, Yulin, 719000, China. Electronic address: [email protected].
⁵ CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China; University of Chinese Academy of Sciences, Beijing 100049, China.
⁶ Liaoning Key Lab of Lignocellulose Chemistry and BioMaterials, Liaoning Collaborative Innovation Center for Lignocellulosic Biorefinery, School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China. Electronic address: [email protected].
⁷ CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: [email protected].

PMID: 39617584
DOI: 10.1016/j.jes.2024.05.025

Abstract

Green and atom-economic depolymerization of lignin remains a great challenge due to its complex non-repetitive structure and the inert property for chemo-digestion. A redox-neutral lignin depolymerization system without the use of extra oxidant and/or reductant over a Co-NC catalyst has been developed in this work, providing the first non-noble metal heterogeneous catalytic system for redox-neutral valorization of lignin. Mechanistic studies based on control reactions and deuterium labeling experiments suggest that the reaction proceeds via a metal-catalyzed dehydrogenation of C_α-OH to afford a carbonyl intermediate, followed by C_β-O bond cleavage (via hydrogenolysis) to afford monophenols and aromatic ketone products. The hydrogen used for the cleavage of the C_β-O bond originates from the alcohol moiety in the substrate, and the cascade dehydrogenation and hydrogenolysis steps are highly coupled, rendering it an efficient and atom-economic process.

Keywords: Aromatic chemical; Co-NC; Depolymerization; Lignin; Mild conditions; β-O-4 model compounds.

MeSH terms

Catalysis
Lignin* / chemistry
Oxidation-Reduction
Polymerization*

Substances

Lignin