桉木硫酸盐法制浆黑液木素提取与表征

Extraction and Characterization of Lignin from Kraft Pulping Black Liquor of Eucalyptus

关键词:  硫酸木素  醇酸木素  提取  红外光谱  核磁共振氢谱

Key Words:SL  CSL  extraction  FT-IR  1HNMR

摘要:以硫酸法和乙醇硫酸法分别从蓝桉硫酸盐法制浆黑液中提取木素获得硫酸木素（SL）和醇酸木素（CSL），通过元素分析、红外光谱、紫外光谱、核磁共振氢谱（1HNMR）对SL和CSL进行分析与表征。结果表明，CSL呈现典型的阔叶材木素特征，主要含愈创木基单元（G）和紫丁香基单元（S），为G-S型木素结构；CSL主要连接键为β-O-4、β-1、β-5、β-β，且含有较多的游离羰基、甲氧基和羟基等活性基团；CSL组成元素主要为C、H、O、N，含量分别为62.55%、5.57%、29.54%、0.15%，其理论分子式为C10H10.68O3.54N0.02；与采用硫酸法从黑液中直接提取的SL相比，CSL的杂官能团及杂分子少一些。

Abstract:The lignins were extracted from kraft pulping black liquor of Eucalyptus by ethanol sulfuric acid and sulfuric acid respectively. These lignins were analysed and characterized by elemental analysis、 FT-IR、 UV spectrum and 1HNMR.The results showed that the lignin separated by ethanol sulfuric acid （CSL） presented typical characteristics of lignin of hardwood, which included syringyl（S） and guaiacyl（G）units, and the amount of S units was higher than the G units; CSL main linkage bonds were β-O-4、 β-1、 β-5、 β-β, and it contained many more free carbonyl, methoxy and hydroxyl groups and other active groups; CSL composition elements were mainly C,H,O,N, and the contents were 62.55%、 5.57%、 29.54%、 0.15%, respectively,its theoretical molecular formula was C10H10.68O3.54N0.02 . Compared with the lignin extracted directly from the black liquor(SL), CSL had less complex functional groups and molecular．