【作者】 朱媛媛；

【导师】 蒋新元；

【作者基本信息】 中南林业科技大学 ， 环境科学与工程， 2008， 硕士

【摘要】 随着工业的迅速发展,废水的种类和数量迅猛增加,水体的污染也日趋广泛和严重,威胁人类的健康和安全。木质素磺酸盐作为一种亚硫酸盐制浆过程中的副产物,如不加以合理利用,将会对环境和人类造成巨大的威胁,因此利用木质素磺酸钠为主体原料,在环境友好的化学介质中合成新型、环保的木质素基吸附材料,用于工业废水的处理,具有现实意义。本文研究了木质素磺酸钠与甲醛的反相悬浮聚合工艺,以及木质素基吸附材料的制备及吸附性能,并进行了结构表征。研究了木质素磺酸钠与甲醛的反相悬浮缩聚反应,以液体石蜡为分散相,添加了少量的非离子型表面活性剂为分散剂,合成了粒径可控的木质素基吸附材料。进一步优化聚合反应条件,详细研究了木钠浓度、相比、分散剂种类和用量、聚合温度、聚合时间、体系酸度和甲醛用量等多种因素对聚合反应和吸附性能的影响。实验考察液体石蜡回收率,对亚甲基蓝溶液、铅离子溶液、镉离子溶液的吸附量等因素,加上成本及能耗因素,得到较适宜的聚合条件为：木质素磺酸钠溶液浓度为50%、以3：1为最佳相比值、分散剂占有机相百分比为2%、温度为90℃、反应体系酸度3mol/L、甲醛含量为木质素磺酸钠质量的9%、聚合时间为1.5h。以阳离子染料亚甲基蓝、Pb2+、Cd2+为对象研究木质素基吸附材料的吸附性能。结果表明,木质素基吸附材料对亚甲基蓝的处理效果不及重金属离子。木质素基吸附材料对溶液中Pb2+和Cd2+的吸附速度快,室温下1h基本达到吸附平衡；温度升高,达到平衡吸附的时间越短；增加Pb2+、Cd2+溶液的初始浓度,木质素吸附材料的平衡吸附量会增大；木质素吸附材料的饱和吸附量分别为33.65mg(Pb2+)/g和30.12mg(Cd2+)/g,Pb2+、Cd2+的吸附等温线符合Langmuir吸附方程,木质素基吸附材料对铅的吸附饱和度和吸附能力大于对镉的吸附。木质素基吸附材料的外观呈棕色不透明圆球状。利用多种现代分析测试手段对木质素基吸附材料的结构进行了表征。扫描电镜SEM、傅立叶变换红外光谱和比表面积等的测试结果表明木质素基吸附材料的外表呈凹凸不平状,具有疏松多孔的结构特征,含有较多的活性基团包括羟基、磺酸基、甲氧基和少量的羰基,有利于金属离子吸附,吸附平均孔径为99.22nm,具有大孔树脂的结构特点。更多还原

【Abstract】 With the rapid development of industry, the kinds and quantities of wastewater has increased fast. The wastewater pollution has become a severe problem that gives potential hazard to environment as well as the public health. Lignosulphonate, which is mostly obtained as a by-product from the red liquors during sulphite pulping process, will bring tremendous harm to environment and people if not utilized reasonably. Therefore, the new environment-friendly lignin-based adsorption material was prepared with sodium lignosulphonate as raw material in an environmental friendly and chemical medium. It has a realistic significance to use for the treatment of industrial wastewater. The inverse suspension polymerization of formaldehyde and lignosulphonate, and the preparation and adsorption performances of lignin-based adsorption material as well as structure characterization were investigated in this paper.The inverse suspension polymerization of formaldehyde and sodium lignosulfonate was investigated. Using the liquid paraffin as the dispersed phase and adding a little of nonionic surfactant as dispersant, lignin-based adsorption material with controllable size range was synthesized.The process conditions for polymerization were optimizd. The influences of sodium lignosulfonate concentration and phase ratio, the type and content of dispersant, polymerization temperature, polymerization time, acidity and formadehyde dosage on the suspension polymerization and adsorption properties were studied in detail. The experiment inspected the coefficient of recovery about liquid paraffin and the adsorption about the solution of methylene blue and lead ion and cadmium ion. Considering these factors above and other factors such as cost and wasted energy, the optimun conditions included 50% sodium lignosulfonate concentration,3:1 of phase ratio,2% of dispersant dosage A,90℃of reaction temperature,3mol/L HCl of acdity,9% of formaldehyde dosage, and 1.5 hours of reaction time.Pb2+, Cd2+ and methylene blue dye were chosen as adsorbates to study the adsorption properties of lignin-based adsorption material. The results showed that lignin-based adsorption material had a worse adsorption for methylene blue dye than for heavy metal ion. The adsorption rate of lignin-based adsorption material for Pb2+ and Cd2+ in aqueous solution was high, and sorption equilibrium was established in about 1 hour. The higher the temperature was, the shorter time it needed to reach the sorption equilibrium. The equilibrium uptake of lignin-based adsorption increased with the development of the initial concentration Pb2+ and Cd2+ in aqueous solution. The saturated adsorption capacities for lignin-based adsorption material were 33.65mg (Pb2+)/g and 30.12mg (Cd2+)/g respectively, and the adsorption isotherms for Pb2+ and Cd2+ followed Langmuir model very well. The adsorption saturation and adsorption capability of lignin-based adsorption for lead were bigger than cadmium.Lignin-based adsorption material appeared to be spheric brown opaque pellets. Many of advanced analytical instruments were used to get more detailed information about its microstructure. Scanning Electron Micrograph (SEM) and Fourier Transform Infrared Absorption Spectra and specific surface area revealed that lignin-based adsorption material had rugged surface and cross section, heterogeneous and porous inner microstructure. It comprised a variety of functional groups, including hydroxyl, sulphonic group, methyoxyl and carbonyl, which were propitious to adsorb heavy metal ion.The average pore size was 99.22nm, and that was the structural characteristic of big pores.更多还原