摘要:本论文采用酸析法制备木质素,通过酸化,过滤,烘干等方法制备木质素。并且,本论文的主要任务是完成木质素制备及应用。
本论文首先以难处理的造纸制浆黑液为原料,对木质素的提取、改性方面的应用进行了详细的实验与研究。滴加不同浓度的盐酸和硫酸,通过对比实验获得酸的浓度对木质素沉淀的影响以及酸种对木质素沉淀的影响,找出木质素沉淀效果最佳的酸性条件。用盐酸沉淀比用硫酸沉淀效果好,硫酸易产生泡沫,反应较为剧烈,不易控制。当pH值=3的时候,木质素沉淀可达90%。
同时,本论文进一步对木质素做了研究,用甲醛、亚硫酸钠还原的方法对得到的木质素进行进一步改性,将木质素改性成为木质素磺酸钠,用红外光谱分析仪确证了其结构。36598
毕业论文关键词: 木质素;酸性;造纸黒液;木质素磺酸钠;红外光谱
The papermaking black liquid extraction lignin research
Abstract: Waste pulp of paper making brings a big load to the environment, in which the main pollution composition is the lignin. Therefore, extraction lignin in pulping waste liquor, papermaking and chemical modification, synthesis has the industrial application value of the products, not only environmental protection significance, more economic significance.
This paper uses the acid out of lignin prepared by acidification, filtration, drying methods such as the preparation of lignin. And, the main task of this thesis is to complete the preparation and application of lignin.
This paper first to difficult paper pulping black liquor as raw material, the application of the extraction of lignin and modified in detail the experiment and research. Drops with different concentrations of hydrochloric acid and sulphuric acid, acid concentration were obtained through the contrast experiment of the effect of lignin precipitation and acid effects on lignin precipitation, find out the best lignin precipitation acidity conditions. Hydrochloric acid precipitation than using sulfuric acid precipitation effect is good, easy generation sulfate bubble, more violent reaction, not easy to control. When the pH = 3, lignin precipitation can amount to 90%.
At the same time, this paper further research is carried out for the lignin, with formaldehyde and sodium sulfite reduction method to further modification of the lignin, the lignin modified become sodium lignin sulfonate, with infrared spectrum analyzer confirmed its structure.
Keywords: lignin;acid;the papermaking;black liquid;Sodium lignin sulfonate;infra-red spectrum(IR spectrum)
目 录
1 绪论 1
1.1 开题依据 1
1.2 造纸黒液 2
1.2.1 造纸黒液 2
1.2.2 造纸黑液的危害 2
1.2.3 造纸黑液处理现状 2
1.3 木质素 3
1.3.1 木质素的结构和性质 3
1.3.2 木质素的理化性质 4
1.4 木质素的提取方法 5
1.4.1 碱析法 5
1.4.2 酸析法 5
1.4.3 絮凝沉淀法 6
1.4.4 超滤法 6
1.5 造纸黑液木质素的资源化利用 6
1.5.1 在农业中的应用 6
1.5.2 木质素在工业中的应用 8
1.5.3 木质素在其他方面的应用 10
1.6 课题的来源、研究意义及内容 10
1.6.1 课题的来源 10
1.6.2 课题的研究意义 11
1.6.3 课题的研究内容 11
2 实验部分 12
2.1 实验原料与仪器设备 12
2.1.1 实验原料 12 造纸黒液提取木质素的研究:http://www.751com.cn/huaxue/lunwen_35115.html