Breakthrough of lignin valorization: A novel alcohol-dichoromethane binary mixture solvent for lignin dissolution with excellent properties

A novel binary solvent system consisting of alcohols (e.g., methanol, ethanol, isopropanol) and dichloromethane was developed as an efficient dissolution system for dissolving various types of lignin. It was found that in this dissolution system, adjusting the volume ratio of alcohol and dichloromethane will significantly affect the solubility of lignin. At the same time, this study proposed that the reason why the solvent can dissolve lignin was the hydrophobic skeleton and hydrophilic groups can be solvated by dichloromethane and alcohols respectively, which significantly promoted the dissolution of lignin. Furthermore, the solvent did not significantly alter the structure of the lignin. The proposed novel solvent is simple, efficient, versatile and flexible, can adapt to the high diversity of lignin, and has broad application prospects.