Pyrolysis characteristics of technical alkali lignin

Pyrolysis characteristics of technical alkali lignin were studied using thermogravimetric analysis and pyrolysis coupled with gas chromatography and mass spectrometry(Py——GC-MS).The effects of heating rate on the pyrolysis characteristics of technical alkali lignin were investigated.The results show that the nonisothermal weight-loss process of technical alkali lignin was composed of four areas, including two peaks of rapid weight-loss below the pyrolysis temperature of 200℃ and between the pyrolysis temperature of 300-500℃.By the analysis of Py——GC——MS,the component of pyrolysis products from technical alkali lignin was very complex,the chief products at 300℃mainly were derived from the decomposition of carbohydrates in technical alkali lignin and other pyrolysis products were from the cleavage of low molecule lignin.The chief pyrolysis products at 450℃ were mainly derived from the cleavage of lignin,such as phenolic compounds,guaiacyl acetone and ferulic acids from lignin-carbohydrates complex.