Klason法木质素慢速热解特性及其动力学机理研究  

THERMAL DECOMPOSITION OF KLASON LIGNIN FROM DIFFERENT BIOMASS BY TG-FTIR

作　　者：周强[1,2] 王秀文[1] 沈德魁[1] 

机构地区：[1]东南大学能源热转换及其过程测控教育部重点实验室,南京210096 [2]国网江苏省电力公司电力科学研究院,南京210012

出　　处：《太阳能学报》2016年第9期2236-2242,共7页Acta Energiae Solaris Sinica

基　　金：国家自然科学基金面上项目(51406114);国家重点基础研究发展(973)计划(2012BC216305)

摘　　要：运用Klason法从4种不同生物质中制备木质素，采用元素及红外分析对不同木质素的化学结构进行表征，运用TG-FTIR研究不同来源木质素慢速热解特性的影响，发现不同来源的木质素热解过程表现为两个主要失重阶段，对应芳香族类化合物的析出与小分子气体的析出过程；其中枫木木质素的热解活性较高，可在较低的温度点（378℃）达到失重最大速率，这与其含有丰富的甲氧基结构有关。在实验分析的基础上建立分阶段反应动力学模型，计算其在不同热解阶段的动力学参数，发现第一阶段活化能主要在19．95～33．66kJ／mol之间，热解第二阶段的活化能在34．82～48．99kJ／mol之间。The structure of lignin extracted from different biomass with Klason method was determined by the Element Analysis and Fourier Transform Infrared Spectroscopy （FTIR）. The absorbance peak of FTIR spectrum around 1120 cm-1 and 1325 cm-1 for maple lignin present the prominent content of syringol-type methypxyl. The thermal degradation of lignin samples in TG-FTIR presents the two main mass-loss stages： the first was attributed to the evolution of aromatic compounds while the second one was the evolution of light gases. The main mass loss peak of maple lignin appears at 378 ℃, exhibiting the most thermally unstable ability among the samples. A separate-stage kinetic model was adopted to calculate the apparent activation energy of the mass-loss stage, presenting the value of 19.95-33.66 kJ/mol for the first stage and 34.82-48.99 kJ/mol for the second stage.

关 键 词：木质素 热解 TG—FTIR 动力学 

分 类 号：TK6[动力工程及工程热物理—生物能]