| 초록 |
Lignin is plant derived biopolymer, which is formed mainly by three phenolic units, known as monolignols and a few carbohydrate moieties. The aim of the present study was to investigate the effect of extraction conditions, mainly severity factor (H-factor = 800, 1100) on the molecular structure of alkaline and organosolv lignins extracted from Korea native Miscanthus. Lignins were characterized by Fourier transform infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA), Gel permeation chromatography (GPC) and Gas chromatography mass spectrometry (GC-MS) analysis to compare thermal properties and chemical composition. After pretreatment, most lignin inter-units and lignin-carbohydrate complex (LCC) linkages were degraded and dissolved in black liquor, with minor amount left in residual pretreated biomass. FTIR analysis of pretreated solid residues revealed reduction in p-hydroxyphenyl (H), guaiacyl (G) and syringyl (S) lignin, FTIR and NMR of these lignins showed S, H and G units. The lignin’s physical and chemical behavior was seen different with respect to the extraction method used. |
