Lignin is considered an ideal natural material for the production of sustainable monophenols.In this study,a microwave-assisted depolymerization(MAD)strategy was developed.The introduction of solvent vapors in the dyn...Lignin is considered an ideal natural material for the production of sustainable monophenols.In this study,a microwave-assisted depolymerization(MAD)strategy was developed.The introduction of solvent vapors in the dynamic vapor flow reaction system was performed to enhance the lignin conversion efficiency.The results showed that no liquid products were generated from the MAD of lignin without solvent vapors.With the introduction of solvents(CH_(3)OH,HCHO,HCOOH,and CH_(2)Cl_(2)),liquid products appeared(especially with CH_(2)Cl_(2),which had the highest yield of 41.9 wt%).Results from gas chromatography/mass spectrometry of liquid products showed that seven kinds of compounds,including guaiacols,phenols,syringols,methoxyphenyls,heterocycles,esters,and aromatics were identified.CH_(2)Cl_(2) can significantly enhance the production of monophenols(guaiacols,phenols,and syringols).The introduction of these solvent vapors can also facilitate the generation of porous char with high Brunauer-Emmett-Teller specific surface areas.Some carbon nanospheres deposited on the surface of the char were obtained with the assistance of CH_(2)Cl_(2).This study provides a facile method for the utilization of lignin in the field of bio-based fine chemicals.展开更多
基金This work was supported by the Foundation of the Key Laboratory of Pulp and Paper Science and Technology of the Ministry of Education of China(No.KF201917)the National Natural Science Foundation of China(31800497).
文摘Lignin is considered an ideal natural material for the production of sustainable monophenols.In this study,a microwave-assisted depolymerization(MAD)strategy was developed.The introduction of solvent vapors in the dynamic vapor flow reaction system was performed to enhance the lignin conversion efficiency.The results showed that no liquid products were generated from the MAD of lignin without solvent vapors.With the introduction of solvents(CH_(3)OH,HCHO,HCOOH,and CH_(2)Cl_(2)),liquid products appeared(especially with CH_(2)Cl_(2),which had the highest yield of 41.9 wt%).Results from gas chromatography/mass spectrometry of liquid products showed that seven kinds of compounds,including guaiacols,phenols,syringols,methoxyphenyls,heterocycles,esters,and aromatics were identified.CH_(2)Cl_(2) can significantly enhance the production of monophenols(guaiacols,phenols,and syringols).The introduction of these solvent vapors can also facilitate the generation of porous char with high Brunauer-Emmett-Teller specific surface areas.Some carbon nanospheres deposited on the surface of the char were obtained with the assistance of CH_(2)Cl_(2).This study provides a facile method for the utilization of lignin in the field of bio-based fine chemicals.
