摘要
【目的】将微波加热与甘油利用相结合的综合炼制工艺用于木质纤维素生物质预处理,探索其在燃料乙醇制备中的可行性,为实现经济可行、经济有效的木质纤维素生物质酶解预处理技术和生物燃料生产提供基础信息。【方法】以银腺杨、日本落叶松、刚竹和柳枝稷为试验材料,采用微波液化法对其进行液化处理,将液化产物分为纤维素、半纤维素和木质素组分,并对纤维素纤维组分进行综合表征。【结果】化学分析结果表明,纤维素纤维具有较高的葡聚糖含量;红外光谱显示,木质素和半纤维素的信号逐渐减弱,说明半纤维素和木质素经液化处理后有效脱除; XRD分析结果表明,纤维素纤维结晶度高、表面积大。【结论】相比原木质纤维素生物质,银腺杨、日本落叶松、刚竹和柳枝稷4种原材料纤维素纤维的酶解糖化效率均有不同程度提升(最高酶解转化率可达70%),液化固体产物——纤维素纤维在制备燃料乙醇中具有广阔的潜力和前景。
【Objective】 The development of a solvolysis process by combining microwave heating and glycerol is a promising method to enhance the economic viability of biorefinery. The application of this technology on the pretreatment of lignocellulosic biomass is of great significance.【Method】 The liquefaction treatment of Populus alba ×P. glandulosa 84 K, Larix kaempferi, Phyllostachys viridis and Panicum virgatum was carried out by microwave liquefaction method. The products were divided into liquid and solid cellulose components. Using cellulose as raw material, the cellulose components were comprehensively characterized.【Result】 The chemical analysis result showed that the cellulose fiber had high glucan content. Infrared spectroscopy showed that the signals of lignin and hemicelluloses gradually weakened, further confirming the effective removal of hemicelluloses and lignin in the liquefaction treatment. The result of XRD analysis showed that the cellulose fibers had high crystallinity and large surface area.【Conclusion】 Compared with the original lignocellulosic biomass, the enzymolysis saccharification efficiency of the cellulose fiber of four kinds of raw materials was not improved to a certain degree, indicating the potential of cellulose fiber in liquefied solid product in the preparation of fuel ethanol.
引文
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