绿液预处理过程中杨木木质素结构的变化  

Structural changes of poplar lignin in the process of green liquor pretreatment

作　　者：孟鑫[1] 吴文娟[1] 金永灿[1] 

机构地区：[1]南京林业大学,江苏省制浆造纸科学与技术重点实验室,江苏南京210037

出　　处：《南京林业大学学报（自然科学版）》2014年第6期93-98,共6页Journal of Nanjing Forestry University：Natural Sciences Edition

基　　金：国家重点基础研究发展计划(2010CB732205);国家自然科学基金项目(31070512;31370571);高等学校博士学科点专项科研基金项目(20133204110006);江苏高校优势学科建设工程资助项目(PAPD)

摘　　要：以绿液(Na2S和Na2CO3)对杨木进行预处理,研究了预处理条件对木质素脱除的影响,并用碱性硝基苯氧化表征预处理后木质素化学结构特征的变化。结果表明:杨木原料木质素的碱性硝基苯氧化产物的总得率为2.61 mmol/g,其木质素非缩合部分紫丁香基结构的硝基苯氧化降解产物与愈疮木基摩尔比n(S+SA)/n(V+VA)为2.0;随着预处理H-因子的升高和用碱量的增加,杨木浆料的木质素脱除率上升,n(S+SA)/n(V+VA)下降;杨木浆料残余木质素的缩合程度随着木质素脱除率的增加而增大,且紫丁香基丙烷结构比愈疮木基丙烷结构在绿液预处理过程中更容易断裂。Green liquor（ Na2 S and Na2CO3） was used as a pretreating regent for poplar wood,and the effects of green liquor pretreatment on lignin removal,and lignin structure were investigated in this paper. The residual lignin in the pretreated poplar was characterized by alkaline nitrobenzene oxidation（ NBO）. The results showed that the total NBO products yield of poplar lignin was 2. 61 mmol / g,and the molar ratio of n（ S ＋ SA） / n（ V ＋ VA） in non-condensed lignin was2. 0. With the increasing of TTA charge and H-factor of green liquor pretreatment,lignin was effectively removed,and the yields of total NBO products,and the molar ratio of n（ S ＋ SA） / n（ V ＋ VA） decreased. The condensation degree of residual lignin in pretreated solid increased with the lignin removal,and the syringyl lignin was more degradable as compared to guaiacyl type in green liquor pretreatment.

关 键 词：杨木 绿液预处理 木质素 碱性硝基苯氧化 

分 类 号：TS743.14[轻工技术与工程—制浆造纸工程]