Highly Efficient Dissolution of Lignin by Eutectic Molecular Liquids

Lignin dissolution is of great importance for the valorization of lignin, and development of novel efficient solvent systems is a crucial topic. Herein, 17 kinds of 1,5-diazabicyclo[5.4.0]-5-undecene-based eutectic molecular liquids (EMLs) were designed for dissolution of industrial lignins. The solubility of lignin in the EMLs significantly depended on the types of the EMLs and lignin. Also the relationship between lignin solubility and the solvatochromic parameters (α, β, and π*) varied significantly based on the EMLs and the types of lignin.