Relevance between chemical structure and pyrolysis behavior of palm kernel shell lignin

Yanqin Huang; Huacai Liu; Hongyou Yuan; Hao Zhan; Xiuzheng Zhuang; Song Yuan; Xiuli Yin; Chuangzhi Wu

doi:10.1016/j.scitotenv.2018.03.238

Relevance between chemical structure and pyrolysis behavior of palm kernel shell lignin

Sci Total Environ. 2018 Aug 15:633:785-795. doi: 10.1016/j.scitotenv.2018.03.238. Epub 2018 Mar 28.

Authors

Yanqin Huang¹, Huacai Liu¹, Hongyou Yuan¹, Hao Zhan², Xiuzheng Zhuang², Song Yuan², Xiuli Yin³, Chuangzhi Wu¹

Affiliations

¹ CAS Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China.
² CAS Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China; University of Chinese of Academy of Sciences, Beijing 10049, China.
³ CAS Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China. Electronic address: xlyin@ms.giec.ac.cn.

PMID: 29602117
DOI: 10.1016/j.scitotenv.2018.03.238

Abstract

Palm kernel shell (PKS) lignin obtained by enzymatic/mild acid hydrolysis (EMAL) was thoroughly elucidated by FTIR (fourier transform infrared), ¹³C-¹H 2D-NMR (nuclear magnetic resonance), quantitative ³¹P NMR combined with DFRC (derivatization followed by reductive cleavage), and Py-GC/MS (pyrolysis-gas chromatography/mass spectrometry) with and without TMAH (tetramethylammonium hydroxide). Pyrolysis behavior was then characterized by TG-FTIR-MS (thermo-gravimetric-FTIR-mass spectrometry) and Py-GC/MS. The PKS lignin is demonstrated to be a p-hydroxyphenyl-guaiacyl-syringyl (H-G-S) lignin with abundances of p-hydrobenzoates and low S/G ratio of 0.15. 2D-NMR indicated that the main substructures are β-O-4-ethers (~85%), and ³¹P NMR/DFRC quantified the total β-O-4 content of 2295μmol/g. Py-GC/MS with and without TMAH confirmed that phenol mainly originated from p-hydroxybenzoates units. Thermal-stability, evolution behavior of typical volatiles, and selectivity of phenolic compounds (H-, G-, S-, C-type) during PKS lignin pyrolysis were explored. Relationship between chemical structure and pyrolysis behavior are also obtained. This work will provide a deep insight to the effective utilization of PKS.

Keywords: Chemical structure; Palm kernel shell lignin; Pyrolysis behavior.