Characterization of Lignins Isolated from Alkali Treated Prehydrolysate of Corn Stover

• Published in: Chinese journal of chemical engineering Vol. 21; no. 4; pp. 427 - 433
• Main Author: 雷鸣柳 张红漫 郑洪波 李媛媛 黄和 徐蓉
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.2013
• Subjects: alkaline pretreatment; Carbon; cellulose ethanol; Corn; corn stover; Derivatives; Hydroxyl groups; lignin structure; Linkages; Lipids; purification; Spectroscopy; Sugars; 傅立叶变换红外光谱; 木质素分离; 玉米秸秆; 碱处理; 纯化过程; 羟基苯基; 表征; 质子核磁共振; lignin structure; alkaline pretreatment; corn stover; cellulose ethanol; purification
• ISSN: 1004-9541; 2210-321X
• DOI: 10.1016/S1004-9541(13)60468-1

Lignins were isolated and purified from alkali treated prehydrolysate of corn stover. The paper presents the structural features of lignins in a series purification processes. Fourier transform infrared spectroscopy, ultraviolet-vis spectroscopy and proton nuclear magnetic resonance spectroscopy were used to analyze the chemical structure. Thermogravimetric analysis was applied to follow the thermal degradation, and wet chemical method was used to determine the sugar content. The results showed that the crude lignin from the prehydrolysate of corn stover was a heterogeneous material of syringyl, guaiacyl and p-hydroxyphenyl units, containing associated polysaccharides, lipids, and melted salts. Some of the crude lignin was chemically linked to hemicelluloses （mainly xylan）. The lipids in crude lignin were probably composed of saturated and/or unsaturated long carbon chains, fatty acids, tdterpenols, waxes, and derivatives of aromatic. The sugar content of purified lignin was less than 2.11%, mainly composed of guaiacyl units. DTGmax of purified lignin was 359 ℃. The majority of the hydroxyl groups were phenolic hydroxyl groups. The main type of linkages in purified lignin was β-O-4. Other types of linkages included β-5, β-β and α-O-4.