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Updated: Jul 20, 2026

Ultrafast Lignin Extraction from Unusual Mediterranean Lignocellulosic Residues
Published on: March 9, 2021
[Study on near-infrared absorption mechanism of alkali lignin]
Xin-sheng Wu1, Yi-min Xie, Huan-bin Liu
1State Key Lab of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China.
Abstract:
The results showed that o-quinone and q-quinone had strong absorption while vanillin had nearly no absorption in the 800-900 nm range of near-infrared spectroscopy through the comparison of their near-infrared absorption spectra. It was proved that quinone structure of alkali lignin had strong absorption in the 800-900 nm range of near-infrared spectroscopy. The change in the absorbency of oleander milled wood lignin treated with NaOH and Na2 S before and after is greater than that in the absorbency of ginkgo milled wood lignin treated with NaOH and Na2 S before and after because more quinone structure was formed in the process of oleander milled wood lignin treated with NaOH and Na2 S. The finding well explained that cooking liquor of hardwood was much stronger than that of softwood while their pulp kappa number was very near.
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