一步法耦合氯化胆碱的汽爆预处理脱木素用于强化酶解
文献类型:学位论文
作者 | ARSLNA NASIR |
答辩日期 | 2020-07-01 |
授予单位 | 中国科学院大学 |
导师 | 王岚 |
关键词 | 玉米秸秆,氯化胆碱,预处理,蒸汽爆破,酶解 |
学位名称 | 硕士 |
学位专业 | 生物化工 |
英文摘要 | 由于面临化石能源日益枯竭,可再生能源替代石化资源将是未来能源利用的重要趋势。以玉米秸秆为代表的生物质燃料生产是当前生物质利用的主流发展方向。由于生物质抗降解屏障的存在,预处理是生物质转化过程的重要步骤。然而,大多数传统的预处理手段无法实现生物质底物组分的有效拆分且预处理效率低,最终降低了生物质转化的经济性。以传统的蒸汽爆破预处理为例,单纯的汽爆处理仅能去除部分半纤维素和纤维素等,对木质素的溶解性较差。基于此,本论文以蒸汽爆破和氯化胆碱组合预处理为核心,来提高脱木质化玉米秸杆的酶解发酵效率。通过优化,用氯化胆碱以1:2.2(w / w),1.0 Mpa,184℃的蒸汽爆破预处理15分钟,处理后玉米秸秆有效地去除了84.7%的木质素和78.9%的木聚糖,实现了纤维素的高效分离。对预处理后的材料进行酶解(10FPU/g)可以实现84.2%的葡聚糖转化率和78.3%的木聚糖转化率。这种联合预处理(ChCl-SE)分别比单纯蒸汽爆破预处理的玉米秸秆和未经处理的玉米秸秆,葡聚糖酶解率分别高出约4.5%和6.4%。为了探究其原因,通过SEM分析后显示出木质素和半纤维素的被溶解从而导致物料的孔隙度上升;通过XRD分析发现纤维素结晶度提高;通过FTIR分析发现聚糖-木质素中甲氧基键的断裂。以上分析证明氯化胆碱耦合汽爆预处理可以有效脱除木质素及半纤维并提高物料的孔隙度,从而促进了物料的酶解过程。;Due to the urgent energy crisis, the replacement of petrochemical resources by renewable energy has become an important trend in the future. Biomass fuel production is an important development direction in biomass utilization. With the gradual deepening of research on the characteristics of lignocellulose materials, pretreatment has become an essential step to promote enzymatic hydrolysis and fermentation. At present, many pretreatments have been developed. Since the original purpose of biotechnology is to achieve cleaner production and higher value utilization, traditional methods do not accomplish these goals well. In order to develop a novel pretreatment and make the treated material with high-value conversion capability and green processing characteristics, the thesis explored a pretreatment method with a steam explosion as the core. The traditional steam explosion pretreatment can only remove part of hemicellulose and cellulose, and it has poor solubility to lignin. In order to solve this problem, choline chloride was innovatively introduced as a steam explosion aid in this study for the pre-treating corn stover, to achieve efficient removal of lignin during the steam explosion process. In this thesis, a combination of steam explosion and choline chloride pretreatment was developed for improving the efficiency of delignification and enzymatic hydrolysis of corn stover. Choline chloride was added with corn stover at a ratio of 1: 2.2 (w/w), and the condition was set to 1.0 MPa, 184 °C for 15 minutes. After pretreatment, the corn stover was found to effectively remove 84.7% of lignin and 78.9% of xylan. During the enzymatic hydrolysis (10 FPU/g) of the pretreated material, it was recorded that it can reach 84.2% glucan conversion rate and 78.3% xylan conversion rate. In this combined pretreatment (ChCl-SE), the glucan digestion rate is about 4.5% and 6.4% higher than untreated corn stalks and pure steam explosion, respectively. In order to explore the reason, SEM analysis showed that the lignin and hemicellulose were dissolved, which caused the porosity of the material to increase; XRD analysis found that the crystallinity of cellulose increased; FTIR analysis found methoxy in glycan-lignin was broken. The above analysis proved that choline chloride coupled steam explosion pretreatment can effectively remove lignin and hemicellulose and increase the porosity of the material, thereby promoting the enzymatic hydrolysis process of the corn stover. |
语种 | 中文 |
源URL | [http://ir.ipe.ac.cn/handle/122111/49643] ![]() |
专题 | 中国科学院过程工程研究所 |
推荐引用方式 GB/T 7714 | ARSLNA NASIR. 一步法耦合氯化胆碱的汽爆预处理脱木素用于强化酶解[D]. 中国科学院大学. 2020. |
入库方式: OAI收割
来源:过程工程研究所
其他版本
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。