Sungkyunkwan University Researchers Develop Sustainable E-Biorefinery to Convert Lignin into High-Value Chemicals Using Electricity

Sungkyunkwan University researchers develop a highly efficient electrochemical process to turn woody lignin into value-added chemicals without external hydrogen.

By: AXL Media

Published: Mar 27, 2026, 6:52 AM EDT

Source: Information for this report was sourced from Sungkyunkwan University External Affairs Division (PR team)

Electrifying the Transition to Carbon Neutrality

The global push for carbon neutrality has intensified the search for sustainable alternatives to fossil-resource-based aromatic chemicals. Lignin, the most carbon-rich component of woody biomass, has long been viewed as a primary candidate for this transition, yet its "recalcitrant" nature has hindered progress. Traditionally, breaking the strong chemical bonds within lignin required extreme temperatures and high-pressure hydrogen atmospheres, leading to high energy consumption and poor selectivity. However, a research team led by Professor Jaehoon Kim at Sungkyunkwan University and Dr. Dong Ki Lee at the Korea Institute of Science and Technology (KIST) has introduced an "e-biorefinery" platform that uses renewable electricity to overcome these structural barriers.

The Mechanics of Hydrogen-Free Depolymerization

The breakthrough centers on an electroreductive strategy employing a 5 wt% Pd/C (palladium on carbon) catalyst. Unlike conventional methods, this process does not require an external supply of hydrogen gas. Instead, it leverages reactive hydrogen formed directly on the catalyst surface during water electrolysis to cleave the stubborn ether bonds in lignin. This dual-action approach allows for simultaneous depolymerization and hydrogenation. By regulating current density, the researchers can precisely control the amount of surface-adsorbed hydrogen, ensuring that the energy is used efficiently to upgrade lignin into useful chemical precursors like cyclohexanol and cyclohexane.

Achieving Precision Under Mild Conditions

Validation of the new process showed remarkable efficiency and selectivity compared to previous electrochemical attempts. Using model compounds that represent the toughest bonds in lignin, the team achieved 100% conversion in as little as 90 minutes at temperatures as low as 30°C to 70°C. For instance, diphenyl ether was converted into cyclohexanol with 99.8% selectivity. The team also discovered that introducing isopropanol as a co-solvent significantly enhanced substrate solubility and hydrogen transfer. These results demonstrate that the aromatic intermediates resulting from bond cleavage can be selectively refined into high-value products under surprisingly mild environmental conditions.