Lignin valorization practices have attracted a great deal of interest in recent years due to the large excess of lignin produced by the pulp and paper industry, together with second-generation bioethanol plants. In this work, a new lignin valorization approach is proposed. It involves ultrafiltration as a fractionation process to separate different molecular weight lignin fractions followed by a hydrogen-free, mild, hydrogenolytic, heterogeneously catalyzed methodology assisted by microwave irradiation to obtain simple phenolic, monomeric products by depolymerization using a nickel-based catalyst. The main products obtained were desaspidinol, syringaldehyde, and syringol; this proves the efficiency of the depolymerization conditions applied. The concentration of these observed compounds increased when the molecular weights of the lignin fractions increased. The applied depolymerization conditions, which take advantage of the use of formic acid as a hydrogen-donating solvent, did not generate any biochar in the systems.
If you can't find a tool you're looking for, please click the link at the top of the page to "Go to old article view". Alternatively, view our Knowledge Base articles for additional help. Your feedback is important to us, so please let us know if you have comments or ideas for improvement.