H_2O_2-[BMIm]Cl改性碱木质素的热解特性研究  

The pyrolysis characteristics of Kraft lignin modified by H_2O_2-[BMIm]Cl

作　　者：杨忠连[1] 张荣芳[1] 陈明强[1] 刘珂[1] 李文婷[1] 

机构地区：[1]安徽理工大学化学工程学院,淮南232001

出　　处：《化工新型材料》2015年第9期134-136,共3页New Chemical Materials

基　　金：国家自然科学基金资助项目(21376007);国家科技支撑计划资助项目(2014BAD02B03);安徽省大学生创新创业训练计划项目(AH201410361214);安徽理工大学引进人才科研启动基金资助项目

摘　　要：采用等体积30%H2O2溶液和离子液体[BMIm]Cl的混合液对提取自造纸黑液的碱木质素氧化降解后,清液加水再生,所得固体改性碱木质素经TGA-FTIR分析,研究了其热解特性。TG/DTG/DTA结果表明,改性碱木质素热解的动力学控制温区在533-649K,且使用Coats-Redfern法在一级热解反应模型下计算得,热解主要发生在574.7K以下,其活化能高达105.675kJ/mol,较改性前高出2.2倍。以10K/min的升温速率分析热解过程所形成的气相FT-IR谱图知,改性碱木质素结构稳定但更容易热解,热解产物中诸如1,2,4-三甲氧基苯、2,6-二甲氧基酚和苯酚等具有邻位和对位二取代官能团的芳香族化合物显著增多。A mixed solution with isopyknic hydrogen peroxide 30% aqueous solution and,an ionic liquid,[BMIm]Cl was used to oxygenize Kraft lignin from black liquor. The pyrolysis behavior of treated Kraft lignin,which was regenerated from the mixed solution and labeled as Modified Kraft lignin（MKL）,was investigated via TGA-FTIR. The kinetic eontrolling temperature range of the MKL pyrolysis was between 533K and 649K approved by TG/DTG/DTA data,and the dominated pyrolysis was occurred below 574.7K, which was calculated from a kinetics model using Coats-Redfern method with a first order pyrolysis reaction. The activation energy of the MKL also reached up to 105. 675kJ/mol, which was 2.2 times greater than the non-treated one. By analyzed the FT IR spectra of the gas evolved during the pyrolysis process at heating rate of 10K/min, the MKL was more stable but pyrolysis easier. The aromatic series with ortho-disubstitution and para dis ubstitution functional groups, such as 1,2,4 trimethoxy benzene, 2,6-dimethoxy-phenol, and phenol, were grown in pyrolysis products.

关 键 词：碱木质素 离子液体 结构改性 热解 

分 类 号：O636.2[理学—高分子化学]