细菌纤维素的改性及其对重金属离子的吸附性能的研究.docx

北京理工大学珠海学院2016届本科毕业论文细菌纤维素的改性及其对重金属离子的吸附性能的研究—磁性纤维素改性材料的制备细菌纤维素的改性及其对重金属离子的吸附性能的研究—磁性纤维素改性材料的制备摘 要天然高分子材料是一种广泛存在于动植物及生物体内的物质，而其中原料出处较多样的且具有较好的降解性的是纤维素；但纤维素在性能上仍存在某些缺点导致其应用范围受到限制，其中相比于植物纤维素，细菌纤维素有较好的透水性和韧性；通过对该材料的复合制备，引入其本身不具备的磁性能可一定程度上扩大纤维素的应用领域本课题以硫酸亚铁、氢氧化钠及氯化铁为原材料，制备磁性纳米粒子四氧化三铁；采用原位合成法，参考四氧化三铁的最佳合成条件，进而给四氧化三铁粒子赋予聚合物载体（纤维素的特殊网络多孔基质），生成磁性纳米材料Fe3O4，复合形成磁性纤维素复合材料；对于磁性纤维素复合材料进行2组对照实验进一步研究性能；主要研究的内容如下：1、 Fe3O4磁性纳米材料的制备该部分的制备通过液相共沉淀法，研究NaOH的浓度、反应PH、滴加速度、熟化温度、铁盐摩尔比、搅拌速度反应条件的影响，合成磁性纳米粒子Fe3O4，优化制备工艺，并吸附重金属铜离子；得出较佳制备条件是：Fe2+：Fe3+为1:1.8、PH=11.5、NaOH的浓度1.5mol/L、熟化温度为50℃、搅拌速度1000r/min；同时对结果进行了讨论，探讨了不同的影响因素下对磁性材料的影响。

2、 磁性纤维素的制备室温下利用直接溶解法配置纤维素均相溶液，以纤维素为载体，通过原位合成法合成磁性纤维素通过探究不同浓度下的纤维素均相溶液及磁性纳米材料Fe3O4的理论质量相对于纤维素质量分数两个影响因素，并吸附重金属铜离子，固定吸附条件为：吸附时长270min、吸附剂投加量1.4g、原始溶液100ml，吸附完成后稀释至检出限，利用原子吸收光谱仪进行检测，得出吸附后浓度及磁性纤维素的最佳合成条件；最佳合成条件下，磁性纤维素吸附铜离子吸附效率为86%；条件是纤维素浓度为0.9%，磁性粒子理论质量为20%（相对于纤维素的质量分数），总铁离子浓度为0.0145mol/L3、 对照实验--磁性纤维素通过探究一定条件下，不同制备方法、改变原位法的沉淀剂、加入表面活性剂PEG对磁性纤维素结果的影响，并吸附重金属铜离子，探究材料吸附性能，并对结果进行讨论关键词：纤维素；磁性；Fe3O4；吸附；磁性纤维素Study on Modification of Bacterial Celluloseand Its Adsorption Properties for Heavy Metal Ions— Preparation of Magnetic Cellulose Modified MaterialsAbstractNatural polymer material is a kind of material widely existing in animals, plants and organisms, and among them, the most extensive raw material source and good degradability is cellulose. As a natural polymer compound, cellulose has certain shortcomings in performance that limit its scope of application. Bacterial cellulose has better water absorption and hydrophilicity than plant cellulose; through the modification of bacterial cellulose and the introduction of magnetic properties that are not possessed by itself, cellulose, a renewable resource, has a wider application range. To prepare magnetic nanoparticles of ferric tetroxide, we choose ferrous sulfate, sodium hydroxide and ferric chloride as raw materials; and then uses the special porous structure of cellulose and in-situ co-precipitation to generate magnetic nanoparticles in the pores of cellulose Particles to prepare magnetic cellulose; and its structure and adsorption performance were studied through three sets of control experiments; the specific research contents are as follows: 1. Preparation of magnetic nanomaterial Fe3O4: For the preparation of this part, magnetic nanoparticle Fe3O4 was prepared by liquid-phase co-precipitation method, we took the molar ratio of iron salts, the reaction pH, the concentration of NaOH and the influence of the dropping acceleration, aging temperature, and stirring speed into consideration, the preparation process is optimized, and the copper ions are adsorbed. The best preparation conditions are: Fe2 +：Fe3 += 1：1.8, PH = 11.5,the concentration of NaOH is 1.5mol / L, the aging temperature is 50 ℃, and the stirring speed is 1000r / min. At the same time, after using different precipitants and adding PEG surfactants, study the difference of magnetic nanomaterial products.2. Preparation of Magnetic Cellulose: A homogeneous solution of cellulose is prepared by direct dissolution at room temperature, and magnetic cellulose is synthesized by in-situ synthesis using cellulose as a carrier. By exploring the two influential factors of the theoretical mass of cellulose homogeneous solution and magnetic nanomaterial Fe3O4 relative to the mass fraction of cellulose at different concentrations, and then copper ions are adsorbed. The fixed adsorption conditions are: adsorption time 270min, the amount of 1.4g absorbent, 100ml of the original solution. Diluting it to the detection limit after adsorption, and use atomic absorption spectrometry to determine the concentration after adsorption and the best preparation conditions of magnetic cellulose. The ion adsorption efficiency is 86%. The best preparation conditions are that the cellulose concentration is 0.9% and the total iron ion concentration is 0.0145mol / L (the theoretical mass of magnetic particles relative to the mass fraction of cellulose is 20%). 3. The control experiments of magnetic cellulose: By exploring the effects of different preparation methods, changing the in-situ precipitating agent, and adding surfactant PEG on the results of magnetic cellulose, and adsorbing copper ions, exploring its adsorption properties, and discussing the results.Keywords: Cellulose magnetic, Fe3O4, adsorption, magnetic cellulose 目录1 绪论 11.1引言 11.2细菌纤维素简介 11.2.1 细菌纤维素的概述 11.2.2 细菌纤维素的应用 21.3纤维素复合材料 31.3.1 纤维素无机复合材料 31.3.2 纤维素有机复合材料 41.3.3 全纤维素复合材料 41.4 磁性纳米材料Fe3O4的制备 51.4.1机械球磨法 51.4.2溶胶-凝胶法 51.4.3 微乳液法 51.4.4 共沉淀法 61.4.5 溶剂热分解法 71.5 磁性纤维素的制备 71.5.1包埋法 71.5.2 单体聚合法 81.5.3 原位合成法 81.5.4表面包覆法 81.6 磁性纤维素的组成及结构 81.7 磁性纤维素的应用 91.7.1 水处理中对重金属离子的吸附 91.7.2 其他领域的应用 111.8 研究目的、意义及主要研究内容 111.8.1 研究目的及意义 111.8.2 研究内容 122 磁性纳米粒子Fe3O4的制备及其吸附铜离子的研究 132.1引言 132.2实验部分 142.2.1主要试剂 142.2.3共沉淀法制备 142.2.4。