纤维素与木质素共热解行为研究及产物分析

Study on co-pyrolysis behavior and product analysis of cellulose and lignin

利用热重分析仪和居里点裂解-气相质谱联用仪进行纤维素和木质素共热解实验,研究纤维素和木质素共热解过程中的相互作用及热解产物分布情况.结果表明:纤维素与木质素共热解过程中存在明显的相互作用,与热解温度和混合比例具有一定相关性.纤维素质量分数较低(30%)时,木质素和纤维素共热解时促进残渣的形成,而抑制了气相产物的形成,并提高了酚的相对产率;纤维素质量分数较高(70%)时,木质素和纤维素在共热解过程中相互促进,抑制了固体残渣的形成和非芳基化合物的形成.在低温区(200~320℃),木质素易活化产生小分子,与纤维素共热解时形成相互促进的作用加速了热失重过程;在高温区,纤维素与木质素共热解促进了残渣的形成,抑制了热解过程.

The characteristic and products distribution of cellulose and lignin co-pyrolysis were studied using thermogravimetric analyzer,and Curie-Point pyrolysis reactor-gas chromatography mass spectrometry to study the co-pyrolysis interaction and products distribution.Results showed that,in the process of co-pyrolysis of cellulose and lignin,there was an obvious interaction,which was correlated with the pyrolysis temperature and mixing ratio.When the mass content of cellulose was lower as 30%,the co-pyrolysis process of lignin and cellulose inhibited the formation of volatiles with high content of phenols,and form more residues;when the mass content of cellulose was higher as 70%,the co-pyrolysis process of lignin and cellulose was enhanced and form less residues with low content of non-aromatic compounds.At low temperature(200-320℃),lignin was easy to be activated to produce small molecules,and accelerates the co-pyrolysis process.At high temperature,the co-pyrolysis of cellulose and lignin promoted the formation of residues with the inhibition effects.