木质素CP-GC-MS法裂解行为研究

Study on Thermal Transformations of Lignin under Curie-point Pyrolysis-GC-MS Conditions

采用居里点热裂解-气相色谱-质谱（CP-GC-MS）联用分析技术，以碱木质素为原料，研究了裂解温度对木质素快速裂解产物组成及其含量的影响。结果表明，木质素居裂解主要生成酚类化合物。GC含量可达60％。低温主要生成愈创木酚结构单元为主体的酚类化合物；在300-360℃之间，酚类化合物GC含量随裂解温度升高而提高，愈创木酚基本单元类化合物占主体，占酚类化合物的90％左右；裂解温度进一步提高，酚类化合物GC含量稳定在60％左右，而愈创木酚基本结构单元类化舍物GC含量随温度升高而降低，主要由于愈创木酚基本结构单元断裂成其他酚类和小分子化合物。

The influence of temperature on the relative content of pyrolysis products obtained by Curie-point pyrolysis from alkalilignin ,which was considered as the model compound of lignin, was investigated by Curie-point pyrolysis-gas chromatography-mass spectroscopy（CP-GC-MS）. The results showed that phenolic compounds up to GC content 60 % were prepared by the Curiepoint pyrolysis of lignin. The process of Curie-point lignin pyrolysis could be divided into three areas. In the area of less than 300 ℃, lignin was pyrolyzed into phenolic compounds mostly made up of guaiacol-unit. In the area between 300 ℃ and 360 ℃, GC content of phenolic compounds were improved greatly with the enhancement of pyrolysis temperature. Guaiacol-unit compounds reached to 90 % of phenolic compounds. In the area of more than 360 ℃, the GC content of phenolic compounds kept to about 60 % , while the GC content of guaiacol-unit compounds was reduced with the increase of pyrolysis temperature, because guaiacol-unit was broken to form other phenolic compounds and small molecular substances, such as methyl alcohol.