Selective conversion of organosolv lignin to p-coumaric acid by catalytic depolymerization using monometallic and bimetallic catalysts
Year: 2026
Type: preprint
Abstract: p-Coumaric acid is particularly valuable due to its applications in cosmetics, materials, and pharmaceuticals, making it an attractive target for lignin valorization. It can be produced from herbaceous crop lignin via catalytic depolymerization. In this study, organosolv lignin was extracted from sugarcane bagasse by ethanosolv pretreatment at 170°C for 1 h. Non-noble metal catalysts, comprising monometallic and bimetallic catalysts, were synthesized by wet impregnation method and evaluated for lignin depolymerization. Effects of reaction parameters, including solvent (methanol, diethyl ether, acetone, tetrahydrofuran, isopropanol and acetonitrile), temperature (160–220°C) and time (1–5 h), were examined to maximize p-coumaric acid yield. Among the studied catalysts, Ni/Al 2 O 3 and Ni-Mo/Al 2 O 3 showed promising activity among each group, with Ni-Mo/Al 2 O 3 emerging as the most effective. Under optimized conditions using methanol as solvent, at 200°C for 3 h under initial 10 bar N 2 , it provided the highest selectivity (15.55%) and yield (12.52%). The reaction pathway was proposed to proceed via hydrogenolysis. Methanol demonstrated outstanding performance by simultaneously serving as a good hydrogen donor and a highly effective lignin solvent. Although catalytic activity declined after the first use, Ni-Mo/Al 2 O 3 retained moderate and consistent activity over three consecutive runs. This work presented the selective conversion of lignin into p-coumaric acid, affirming the high potential of the developed catalytic system and reaction parameters to valorize agricultural waste into sustainable chemicals.
Source: Research Square
Language: English
Topic: Lignin and Wood Chemistry
Subfield: Process Chemistry and Technology
Field: Chemical Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7163003795