超临界二氧化碳辅助乙醇制浆脱木素及木素结构变化分析  

Supercritical CO2 assisted ethanol delignification and analysis in structural changes of lignin

作　　者：朱宏伟 刘晶 王兴 周景辉 ZHU Hongwei;LIU Jing;WANG Xing;ZHOU Jinghui(School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China;Yueyang Forest and Paper Company Limited, Yueyang 414000, China)

机构地区：[1]大连工业大学轻工与化学工程学院,辽宁大连116034 [2]岳阳林纸股份有限公司,湖南岳阳414000

出　　处：《大连工业大学学报》2020年第4期255-264,共10页Journal of Dalian Polytechnic University

基　　金：国家自然科学基金项目(21908014).

摘　　要：采用超临界二氧化碳辅助乙醇制浆(SC-AEOP),研究了不同制浆温度和保温时间对浆料性能的影响,考察了温度和时间对浆料得率、成分和卡伯值的影响。通过超临界二氧化碳辅助,乙醇制浆的制浆温度可降低20℃。为了明确SC-AEOP过程中木素结构变化,分别对原料木片中酶解木素、残余在SC-AEOP浆料中的木素(SCEP-RL)和溶解在SC-AEOP蒸煮液中的木素(SCEP-DL)进行了13C核磁、31P核磁和2D-HSQC核磁等分析。结果表明,在SC-AEOP制浆过程中木素的芳基醚键发生了大量断裂并且形成了新的碳碳键结构;SCEP-RL和SCEP-DL中木素的酚羟基和羧基含量均高于EHL。The supercritical carbon dioxide(SC-CO2)was employed to assist the delignification during auto-catalyzed ethanol organosolv pulping(AEOP)process.The effects of pulping temperature and time on the properties of pulps,e.g.,yields,compositions and Kappa values,were studied.The results showed that the pulping temperature during AEOP process could be reduced by 20℃after employment of supercritical carbon dioxide.To conclude the structural changes of lignin during SC-AEOP process,enzymatic hydrolysis lignin(EHL)in original poplar chips,residual lignin in SC-AEOP residues(SCEP-RL)and lignin dissolved in the SC-AEOP liquors(SCEP-DL)were sequentially isolated and systematically characterized by quantitative 13C-NMR,31P-NMR and 2D-HSQC NMR techniques.The results showed that amounts of aryl ether linkages in lignin were cleaved and new C-C units were formed during SC-AEOP process.The contents of free phenolic hydroxyl groups and carboxylic acids in SCEP-RL and SCEP-DL were higher than those in EHL.

关 键 词：超临界二氧化碳 乙醇制浆 木素 脱木素 

分 类 号：TS727.2[轻工技术与工程—制浆造纸工程]