Structural changes in lignin during integrated process of steam explosion followed by alkaline hydrogen peroxide of Eucommia ulmoides Oliver and its effect on enzymatic hydrolysis
| Autor: | Zhi-Wen Wang, Ming-Qiang Zhu, Jia-Long Wen, Yin-Quan Su, Run-Cang Sun, Qin Wei |
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| Rok vydání: | 2015 |
| Předmět: |
ved/biology
Mechanical Engineering ved/biology.organism_classification_rank.species technology industry and agriculture food and beverages Eucommia ulmoides Ether Building and Construction Management Monitoring Policy and Law complex mixtures chemistry.chemical_compound Hydrolysis General Energy chemistry Enzymatic hydrolysis Organic chemistry Lignin Cellulose Hydrogen peroxide Steam explosion |
| Zdroj: | Applied Energy. 158:233-242 |
| ISSN: | 0306-2619 |
| Popis: | Eucommia ulmoides Oliver (EU) wood was successively treated by a combined system based on steam explosion pretreatment (SEP) and alkaline hydrogen peroxide post-treatment (AHPP). In this case, SEP was to disrupt the lignocellulosic structure, and the subsequent AHPP process was to isolate the high-purity lignin and cellulose-rich substrates. Results showed that the lignin fractions obtained during the AHPP exhibited smaller molecular weights, narrow polydispersity, less phenolic OH groups and lower syringyl/guaiacyl ratios (S/G) than those of the milled wood lignin (SE MWL ) obtained from the only steam exploded EU. NMR characterization of lignin revealed that the AHPP process has a slight effect on the composition and molecular characteristic of lignin, and the lignin isolated had lower amounts of substructures (aryl- β -ether, resinol, and phenylcoumaran linkages) as compared to those in SE MWL . Moreover, the subsequent SEP followed by AHPP process enhanced the enzymatic hydrolysis of cellulose-rich substrates to a maximum value of 91.69%. It was found that the synergistic treatment removed most of lignin, degraded hemicelluloses, and incurred a higher crystalline index and surface area of the cellulose-rich substrates as compared to the only steam explosion pretreatment. The combination of the SEP and AHPP processes is an environmentally benign and advantageous scheme for the production of high-purity lignin and cellulose-rich substrates, which will be further transformed into the value-added biomaterials and bioethanol. |
| Databáze: | OpenAIRE |
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