摘 要：近年来，随着农业和农村经济的发展，农业生产过程中产生的废弃物不断增加，造成大量农作物秸秆剩余。这些燃料完全可以变废为宝，成为应对气候变暖、解决环境问题、缓解能源危机的有力法宝。农作物光合作用的产物有一半以上存在于秸秆中，秸秆富含氮、磷、钾、钙、镁等，是一种具有多用途的可再生的生物资源。本文采用稻草秸秆为主要原料，通过碱法抽提木质素、酸析木素等步骤，分别采用ZSM-5X型分子筛、三氯化铁及磷酸氢二钾对ZSM-5X分子筛进行改性、以及常用的硫酸铜催化剂对酶法木质素进行催化氧化降解实验，以对羟基苯甲醛、香草醛及丁香醛的总产量为指标，比较前三种催化剂与硫酸铜的催化效果，进而分析工艺的可行性。实验结果：②号瓶中用三氯化铁改性过的分子筛催化得到产量为0.519g，④号瓶中用硫酸铜催化得到的产量为0.527g；⑥号瓶中用过量的三氯化铁改性过的分子筛催化得到的产量为0.559g，⑧号瓶中用过量的硫酸铜催化得到的产量为0.638g。结果表明：硫酸铜催化效果明显，用三氯化铁对ZSM-5X分子筛改性过后的催化剂，催化效果最接近于硫酸铜。用氯化亚铁改性过分子筛的催化工艺为本实验得到的最优工艺。67012
毕业论文关键词： 稻草，碱法抽提，酸析木素，分子筛，催化氧化降解
Abstract:In recent years, with the development of agriculture and rural economy, waste produced in the process of agricultural production is increasing, resulting in a large number of crop straws. These waste can be changed into fuels, as treasure, as a powerful weapon to alleviate the energy crisis, climate warming, environmental problems. The product of crop photosynthesis more than half of the straw is rich in nitrogen, phosphorus, straw, potassium, calcium and magnesium, is a versatile renewable biological resources. This paper is mainly concerned with catalytic pyrolysis of alkaline extracted lignin with modified zeolites. Its chief objective is to optimize the catalytic pyrolysis reaction conditions and improve the yield of aromatic aldehydes. In this work, we have used zeolite ZSM-5 modified by different methods (Fe3+ or PO43- modified) to catalyze the pyrolysis process of alkaline extracted lignin for preparation of aromatic aldehydes and compare their properties with non-catalytic pyrolysis experiments. The effects of the catalytic temperature, reaction time, and the amount of catalyst on the experimental results were investigated. The experimental results demonstrated that ZSM-5 modified by Fe3+ was the optimized catalyst which was closest to copper.
Keywords：rice straw；alkali extraction；acid precipitation lignin；molecular sieve；catalytic oxidation
目 录
1 绪论 4
1.1 选题背景和意义 4
1.2 本论文研究的内容 4
2.实验材料与步骤 5
2.1实验材料与仪器 5
2.2实验步骤 5
2.2.1酸析木质素的制备 5
2.2.2 ZSM-5X型分子筛的改性 5
2.2.3催化剂优化实验 6
2.2.4检测方法 6
3结果与讨论 9
结 论 13
参 考 文 献 14
致 谢 15
酶法木质素催化氧化降解反应条件的优化:http://www.751com.cn/huaxue/lunwen_75091.html