A two-step process for pre-hydrolysis of hemicellulose in pulp-impregnated effluent with high alkali concentration to improve xylose production
| Autor: | Song Wu, Meitong Jin, Nan Qiao, Xinhong Du, Dayu Yu, Yunfen Shi, Lei Wang |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Environmental Engineering
Health Toxicology and Mutagenesis 0211 other engineering and technologies 02 engineering and technology 010501 environmental sciences engineering.material Xylose Alkalies 01 natural sciences chemistry.chemical_compound Hydrolysis Polysaccharides Enzymatic hydrolysis Environmental Chemistry Hemicellulose Waste Management and Disposal Effluent 0105 earth and related environmental sciences 021110 strategic defence & security studies Chemistry Pulp (paper) Pollution Wastewater engineering Acid hydrolysis Nuclear chemistry |
| Zdroj: | Journal of hazardous materials. 402 |
| ISSN: | 1873-3336 |
| Popis: | The viscose fiber production process is accompanied by the accumulation of pulp-impregnated effluent (PIE), including hemicellulose and large amounts of alkali, and discharge of PIE will cause environment pollution. This paper aims to relieve the inhibition of high concentration of alkali on xylose production from hydrolysis of hemicellulose in PIE. Based on the fact that solid acid uses H+ at the acid sites to exchange with cations in PIE and can be recycled, a two-step method including an extra pretreatment process before pre-hydrolysis (SPP) is proposed. After the alkali was removed by the H+ dissociated from solid acid in the extra pretreatment process, the pH of PIE dropped from 14 to 4, and the content of Na+ and proteins was reduced by 99.13 % and 78.51 %, respectively. After SPP, the polymerization degree of the hemicellulose decreased by 73.4 %, and the subsequent enzymatic hydrolysis process was promoted. Finally, the xylose yield of SPP followed by enzymatic hydrolysis reached 57.15 g/L, which was 145.38 % more than that of enzymatic hydrolysis alone. The load of a downstream ion purification procedure was relieved compared to that of inorganic acid hydrolysis. The development of SPP contributes to the resource utilization of high alkali concentration wastewater. |
| Databáze: | OpenAIRE |
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