摘要：木质纤维素是世界上最丰富的可再生生物质，主要由纤维素、半纤维素和木质素组成。正在开发的预处理技术的目的是为将原始木质纤维素生物质转化成糖和木质素提供可行的生产工艺，从而为市场和环境提供可持续的生物质产品。木质纤维素生物质预处理技术包括生物、机械、化学方法和机械-化学预处理。这些技术中，生物预处理的水解率低，所需的停留时间长；机械预处理减小颗粒的尺寸，增加了表面积和体积比，使材料更容易处理；化学预处理包括弱酸、强酸和碱的水解等方法，效率相对较高，在工业中的应用比较广泛；机械-化学法结合了机械与化学反应，包括蒸汽爆炸、氨纤维爆破和CO2爆炸。但现有的这些预处理过程中存在的障碍主要包括了纤维素和木质素的分离不足、抑制了乙醇发酵的副产物的形成、化学品和能源的高度使用以及大量废物的生产。因此，最佳预处理工艺的选择不仅要根据其产率，也要依据其他的参数，如经济评估和环境影响。92916

毕业论文关键词：木质纤维素、预处理、半纤维素、木质素、化学

摘 要 ： Lignocellulose, the most abundant renewable biomass on earth, is composed mainly of cellulose, hemicellulose and lignin。 The overall goal of the pretreatment routes being developed is to convert raw lignocellulosic biomass into its composing sugars and lignin in a market competitive and  environmentally sustainable way。 Pretreatment technologies for lignocellulosic biomass include biological, mechanical, chemical methods and combined chemical and mechanical pretreatment。 The rate of biological hydrolysis is usually very low, so this pretreatment requires long residence times。Mechanical pretreatment reduces the size of the particles, increases the surface area and volume ratio, making the material easier to handle。Chemical pretreatment includes weak acid hydrolysis, strong acid hydrolysis and alkali hydrolysis methods, which efficiency is relatively high, in the industrial application of a wide range。 Mechanical-chemical methods combine mechanical and chemical reactions, including steam explosion, Ammonia fibre explosion and CO2 explosions。Obstacles in the existing pretreatment  processes include insufficient separation of cellulose and lignin , formation of by-products that inhibit ethanol fermentation, high use of chemicals and energy,  and considerable waste production。 Thus, the choice of the optimum pretreatment process depends very much on the objective of the biomass pretreatment, its economic assessment and environmental impact。

关 键 词 ： Lignocellulosic、Pretreatment、Hemicellulose、Lignin、Chemical

目 录

1前言 5

2木质纤维素生物质的物理和化学特性 5

2。1组成 5

2。2组分间的化学作用 7

2。2。1共聚物的联系 7

2。2。2复合机构 8

2。2。3纤维素成分的官能团和化学性质 8

2。3发酵抑制剂的形成 10

2。3。1糖的降解产物 10

2。3。2木质素降解产物 10

2。3。3醋酸 11

2。3。4抑制提取物 11

2。3。5重金属离子 11

2。3。6总结 11

3预处理方法的概述