| 초록 |
Lignin, which has a complex chemical structure and properties including a polydisperse molecular weight distribution, has limited value-added utilization. Fractionation of lignin into several homogeneous fractions is one of the promising methods for utilizing lignin commercially and realize upgraded lignin valorization. Kenaf organosolv lignin(OL) was sequentially fractionated by five organic solvents (diethyl ether: F1, chloroform: F2, 2-butanone: F3, acetone: F4, and acetic acid: F5). Lignin’s fractions were characterized by GPC, EA, FTIR and TGA and were compared in terms of molecular weight distribution and functional groups. Yields of five OL fractions F1 to F5 were 7.1%, 46.4%, 10.9%, 7.1%, and 5.0%, respectively. The average molecular weight(Mw) of OL, F1 (lowest molecular weight fraction), F2, F3, and F4 (highest molecular weight fraction) were 2424, 1220, 2021, 2589 and 3415 Da, while that of F5 could not be determined due to its low solubility in GPC solvent. In this study, it was confirmed that lignin with a homogeneous structure according to molecular weight was formed through sequential solvent fractionation. |
