摘要
以毛竹竹黄为原料,研究其木质素在稀酸预处理过程中的结构变化。依据Bjrkman的方法分离纯化得到竹黄和稀酸预处理竹黄的磨木木质素,采用红外光谱(FT-IR)和核磁共振定量^(13)C谱对两个木质素样品结构进行分析。FT-IR和定量^(13)C谱图表明:在酸性条件下,竹黄木质素紫丁香基单元中醚化的联接键发生断裂,S/G比值由1.3降低为1.1。木质素在稀硫酸预处理过程中发生缩合反应,主要发生在愈创木基单元上。木质素芳环上C—O键含量由196.1/100C_9降低为187.7/100C_9,C—H键含量由219.4/100C_9降低为205.7/100C_9,C—C键含量由179.6/100C_9提高为190.3/100C_9,缩合度由31.4%提高为35.2%。
The effect of dilute acid pretreatment on the lignin structure of Moso bamboo inner skin was investigated. Thebamboo inner skin ball-milled lignins （MWLs） were isolated before and after dilute sulfuric acid pretreatment, accordingto the isolation method developed by Bj6rkman. The structures of the MWLs were characterized by fourier transform infra-red spectroscopy （FT-IR） and nuclear magnetic resonance （NMR）. The 13C-NMR spectra showed that the etherifiedlinkages in syringyl units were depolymerized during the acid pretreatment. After pretreatment, the S/G ratio of ligninwas reduced from 1.3 to 1.1. Meanwhile, some lignins were condensed during the acid pretreatment, inducing the con-densation degree increased from 31.4 % to 35.2 %. The amount of C--O and C--H linkages in the lignin were reducedfrom 196.1/100C9 and 219. 4/100C9 to 187. 7/100C9 and 205. 7/100C9, respectively. While, the C--C linkages in thelignin were increased from 179. 6/100C9 to 190. 3/100C9.
出处
《林业工程学报》
北大核心
2016年第1期55-60,共6页
Journal of Forestry Engineering
基金
国家自然科学基金资助项目(31570561)
江苏省高校优势学科建设工程资助项目(PAPD)
关键词
竹黄
稀酸预处理
木质素
核磁共振
定量分析
bamboo inner skin
dilute acid pretreatment
lignin
NMR
quantitative analysis
作者简介
黄曹兴，男，博士生，研究领域为林产化学加工。通信作者：勇强，男，教授。E-mail：swhx@njfu．com．cn
