Insight into the solvent, temperature and time effects on the hydrogenolysis of hydrolyzed lignin.
The aim of this study is to explore the reaction mediums and conditions for producing high yield of valuable monomers from concentrated sulfuric acid hydrolyzed lignin. The solvent, temperature and time effects on the hydrogenolysis of hydrolyzed lignin were investigated under the catalysis of Pd/C and CrCl3. Supercritical methanol exhibits the best depolymerization performance, because of its unique diffusion, dissolution and acid-base properties. Afterwards, the influence of reaction temperature and time on depolymerization, repolymerization and coking during hydrogenolysis was examined in methanol. The high temperature is found to favor the depolymerization, with the β-O-4 linkages cleaved significantly. However, the repolymerization is promoted simultaneously, and a high amount of β-β groups form. These reactions are in constant competition with each other and the repolymerization is preferred at excessive high temperature, producing bulk char residues, that is coking. This study will provide a beneficial reference for the maximization of lignin waste valorization.
Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, PR China; Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
Riyang
R
Shu
Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, PR China; Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China.
Qi
Q
Zhang
Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, PR China; Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China.
Longlong
L
Ma
Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, PR China; Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China. Electronic address: xuying@ms.giec.ac.cn.
Ying
Y
Xu
Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, PR China; Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
Pengru
P
Chen
Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, PR China; Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China.
Chenguang
C
Wang
Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, PR China; Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China.
Tiejun
T
Wang
D002384:Catalysis; D006358:Hot Temperature; D006868:Hydrolysis; D008031:Lignin / Q000737:chemistry / Q000378:metabolism*; D000432:Methanol / Q000737:chemistry; D058105:Polymerization; D012997:Solvents / Q000737:chemistry / Q000378:metabolism*; D013696:Temperature; D013997:Time Factors
D012997:Solvents; D008031:Lignin; D000432:Methanol
Hydrogenolysis; Hydrolyzed lignin; Repolymerization; Solvent effect; Temperature effect