Hemicellulose pyrolysis mechanism based on functional group evolutions by two-dimensional perturbation correlation infrared spectroscopy

FUEL

卷:267

Article

Yang, Haiping¹  Li, Shujuan¹  Liu, Biao^1,2  Chen, Yingquan¹  Xiao, Jianjun¹  Dong, Zhiguo¹  Gong, Meng¹  Chen, Hanping¹ 

[1] Huazhong Univ Sci & Technol, State Key Lab Coal Combust, Wuhan 430074, Peoples R China

[2] State Grid Hunan Integrated Energy Serv Co Ltd, Changsha 410007, Peoples R China

关键词: Hemicellulose;    Pyrolysis;    Structural evolution;    Two-dimensional perturbation correlation infrared spectroscopy;   

DOI  :  10.1016/j.fuel.2020.117302

来源: Elsevier

【 摘 要 】

To gain an improved understanding of the hemicellulose pyrolysis mechanism, two-dimensional correlation infrared spectroscopy (2D-PCIS) was employed to analyze the functional group evolution in xylan chars between 200 and 600 degrees C, and through combination with the obtained volatiles releasing properties. Simultaneously, the pathway of xylan decomposition was deduced to illustrate the pyrolysis mechanism. The depolymerization and ring-opening reactions of xylan started at 200 degrees C. After that, it was mainly xylan matrix degradation reaction to form char structure which mainly consisted of phenyl rings and oxygen-containing cyclic compounds with aliphatic chains. With temperature increasing (300-450 degrees C), the decarbonylation reaction, removal of C=C and fatty chains reactions were intensified and the molecular structures of xylan char reconstructed to form fusedring compounds on the order of 1 x 2 and 2 x 2 through condensation. Dehydrogenation and polycondensation reaction of xylan increased at higher temperature (450-600 degrees C). The char structure was composed of high-order fused-ring compounds, and the production of H-2 and CH4 increased greatly.

【 授权许可】

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