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Title: Catalytic Hydrolytic Cleavage and Oxy-Cleavage of Lignin Linkages

Abstract

In this work, new strategies involving organic bases were evaluated to depolymerize lignin to reduced molecular fragments in aqueous medium. NaOH as an inorganic base was also investigated as a reference. Full nature lignin samples are used for the study. As research tools to unravel the complexity of the macro lignin structure and bulky molecular size under this study, size exclusion chromatography and high resolution mass spectrometric analysis, typically used for protein characterizations, were used to follow the progress of lignin depolymerisation by measuring the molecular weight distribution of the products and determining the key molecular fingerprints, respectively. The results show that sodium phenoxide and guanidine carbonate are effective catalysts for lignin depolymerization. It is observed that there exists a synergism between H2O2 and the organic base, which is strongest with guanidine carbonate.

Authors:
; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1132683
Report Number(s):
PNNL-SA-97973
28793
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Molecular Catalysis. A, Chemical., 388-389:35-40
Country of Publication:
United States
Language:
English
Subject:
Environmental Molecular Sciences Laboratory

Citation Formats

Xia, Guanguang, Chen, Baowei, Zhang, Rui, and Zhang, Z. Conrad. Catalytic Hydrolytic Cleavage and Oxy-Cleavage of Lignin Linkages. United States: N. p., 2014. Web. doi:10.1016/j.molcata.2013.08.016.
Xia, Guanguang, Chen, Baowei, Zhang, Rui, & Zhang, Z. Conrad. Catalytic Hydrolytic Cleavage and Oxy-Cleavage of Lignin Linkages. United States. doi:10.1016/j.molcata.2013.08.016.
Xia, Guanguang, Chen, Baowei, Zhang, Rui, and Zhang, Z. Conrad. Sat . "Catalytic Hydrolytic Cleavage and Oxy-Cleavage of Lignin Linkages". United States. doi:10.1016/j.molcata.2013.08.016.
@article{osti_1132683,
title = {Catalytic Hydrolytic Cleavage and Oxy-Cleavage of Lignin Linkages},
author = {Xia, Guanguang and Chen, Baowei and Zhang, Rui and Zhang, Z. Conrad},
abstractNote = {In this work, new strategies involving organic bases were evaluated to depolymerize lignin to reduced molecular fragments in aqueous medium. NaOH as an inorganic base was also investigated as a reference. Full nature lignin samples are used for the study. As research tools to unravel the complexity of the macro lignin structure and bulky molecular size under this study, size exclusion chromatography and high resolution mass spectrometric analysis, typically used for protein characterizations, were used to follow the progress of lignin depolymerisation by measuring the molecular weight distribution of the products and determining the key molecular fingerprints, respectively. The results show that sodium phenoxide and guanidine carbonate are effective catalysts for lignin depolymerization. It is observed that there exists a synergism between H2O2 and the organic base, which is strongest with guanidine carbonate.},
doi = {10.1016/j.molcata.2013.08.016},
journal = {Journal of Molecular Catalysis. A, Chemical., 388-389:35-40},
number = ,
volume = ,
place = {United States},
year = {Sat Jul 26 00:00:00 EDT 2014},
month = {Sat Jul 26 00:00:00 EDT 2014}
}
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