Investigation of [Emim][OAc] as a mild pretreatment solvent for enhancing the sulfonation efficiency of alkali lignin
| Autor: | Zhili Zhang, Rendang Yang, Yao Xianping, Wenhua Gao |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
0106 biological sciences
Aqueous solution Chemistry General Chemical Engineering 02 engineering and technology General Chemistry 021001 nanoscience & nanotechnology 01 natural sciences Standard enthalpy of formation Gibbs free energy Solvent chemistry.chemical_compound symbols.namesake 010608 biotechnology symbols Lignin Organic chemistry Solubility Fourier transform infrared spectroscopy 0210 nano-technology Dissolution Nuclear chemistry |
| Zdroj: | RSC Advances. 7:31009-31017 |
| ISSN: | 2046-2069 |
| DOI: | 10.1039/c7ra03877a |
| Popis: | The chemical recalcitrance and complex structure of lignin macromolecules make them difficult to meet the needs of real production processes and limit their high-value utilization. Hence, an efficient and economic method to break the recalcitrance under mild conditions is meaningful and purposeful. In this study, 1-ethyl-3-methylimidazolium acetate ([Emim][OAc]) was employed to pretreat alkali lignin (AL). Then the dissolving properties and behaviors of AL in [Emim][OAc] were investigated. In addition, the apparent standard Gibbs energy change (ΔG°), the standard apparent entropy change (ΔS°), and the apparent standard enthalpy energy change (ΔH°) of lignin in [Emim][OAc] were estimated by using the experimental solubility data. The regenerated lignin (RL) from [Emim][OAc] was also analyzed by Fourier transform infrared spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), GPC, TG analysis and 31P-NMR spectroscopy. Importantly, the water solubility and sulfonated degree of RL were increased by 14.6% and 33.6%, respectively. Such results imply that [Emim][OAc] pretreatment could improve the sulfonation efficiency and make the development of lignin-based products a real possibility. |
| Databáze: | OpenAIRE |
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