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Updated: Jun 18, 2025

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
Activity and product distribution in Ni-Co and Ni-Cu catalyst-mediated lignin depolymerization into phenolic
Remigius Nnadozie Ewuzie1, Jackson Robinson Genza1, Ahmad Zuhairi Abdullah2
1School of Chemical Engineering, Universiti Sains Malaysia, Nibong Tebal, 14300, Seberang Perai, Penang, Malaysia.
Abstract:
Lignin, a vital renewable biopolymer, serves as the Earth's primary source of aromatics and carbon. Its depolymerization presents significant potential for producing phenolic fine chemicals. This study assesses promoted Ni-based bimetallic catalysts (Ni-Co/C and Ni-Cu/C) supported on activated carbon in isopropanol for lignin depolymerization, compared to monometallic counterparts. BET, SEM, EDX, and XPS analyses highlight their physicochemical properties and promotional effects, enhancing hydrogenolysis activity and hydrogen transformation. Reaction parameter exploration elucidates the influence on lignin depolymerization, with cobalt and copper as promoters notably increasing conversion and monomer yield. Ni-Co/C exhibits the highest lignin conversion (94.2%) and maximum monomer yield (53.1 wt%) under specified conditions, with lower activation energy (36.1 kJ/mol) and higher turnover frequency (31.6 h-1) compared to Ni/C. FT-IR, GPC, GC-FID, and GC-MS analyses confirm effective depolymerization, identifying 20 monomer products. Proposed reaction mechanisms underscore the potential of Ni-based bimetallic catalysts for lignin valorization, offering insights into developing efficient catalytic systems for lignin hydrogenolysis. This research enhances understanding and facilitates the development of selective catalytic processes for lignin valorization.
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