氨基功能化高分子微球制备、表面修饰以及去除废水中的Cr(VI)
文献类型：学位论文
| 作者 | 李鹏飞 |
| 学位类别 | 硕士 |
| 答辩日期 | 2012-05-14 |
| 授予单位 | 中国科学院研究生院 |
| 导师 | 刘会洲 ; 杨良嵘 |
| 关键词 | PGMA 单分散 超顺磁性 铈盐引发 PEI 氨基 Cr(VI) |
| 其他题名 | Preparation and Surface Modification of Superparamagnetic PGMA Microspheres with Amino Groups for Adsorption of Cr(VI) in Waste Water |
| 学位专业 | 化学工程 |
| 中文摘要 | 基于高分子微球的分离技术在许多领域展现出广阔而诱人的应用前景，如环境领域、生化分离、催化剂制备等。然而，目前高分子微球的制备和应用研究主要还局限在实验室分析和医疗诊断规模，将其发展到环境领域的大规模分离纯化还面临着许多问题和挑战，集中体现在如何制备性能优良的高分子微球，实现规模化生产，降低生产成本；如何提高高分子微球的表面功能基团的含量及高分子微球的吸附容量等方面。 针对上述问题，本文系统的开展了高分子微球的制备、渗磁制备磁性高分子微球、表面功能化修饰及其在脱除废水中Cr(VI)的研究工作。主要取得了以下几个方面的创新性研究结果： (1) 采用分散聚合法在不同条件下合成PGMA高分子微球，寻求最合适的操作条件，合成单分散的、粒度均一的微米级高分子微球。并且通过扫描电镜(SEM)和傅立叶变换红外光谱(FTIR)对其粒径、形貌、结构、组成进行表征。 (2) 通过对单分散的PGMA高分子微球进行表面修饰，制备了四种高分子微球，第一是采用渗透沉积法合成单分散的磁性PGMA-NH2高分子微球。第二是采用铈盐引发接枝聚合生成的单分散的、表面富含“须状”氨基高分子链的g-PGMA-NH2高分子微球。第三是采用不同分子量的PEI氨解获得的PGMA-NH2高分子微球。第四是采用不同粒径的高分子微球，氨解开环反应后得到的高分子微球。并且分别通过扫描电镜(SEM)、傅立叶变换红外光谱(FTIR)、X射线衍射(XRD)三种方法进行高分子微球粒径、形貌、结构、组成和磁性能等的表征。 (3) 在此基础上，着重研究了磁性PGMA-NH2高分子微球以及表面富含“须状”PEI氨基高分子链的g-PGMA-NH2高分子微球对于Cr(VI)的吸附性能及吸附机理。结果表明： 磁性PGMA-NH2高分子微球对Cr(VI)有较高的吸附量，等温吸附数据符合Langmuir模型，在T＝298.15 K，pH＝4.5时，吸附剂的饱和吸附容量为263.16 mg/g。吸附量与废水中Cr(VI)的离子形式有关，pH=1.5时吸附效果最好，在15 min内达到平衡。吸附以离子交换与静电引力为主，自发进行，焓变ΔHo＝9.63 kJ/mol。 表面富含“须状”氨基高分子链的g-PGMA-NH2高分子微球对Cr(VI)有较好的吸附效果。结果显示：等温吸附数据符合Langmuir模型，在T＝298.15 K，pH＝4.5时，吸附剂的饱和吸附容量为500.00 mg/g。吸附量与废水中Cr(VI)的离子形式有关，pH=1.5时吸附效果最好，在30 min内达到平衡。吸附以离子交换与静电引力为主，自发进行，焓变ΔHo＝3.61 kJ/mol。 根据Langmuir模型计算所得PGMA-PEI600，PGMA-PEI1,800和PGMA-PEI10,000高分子微球的饱和吸附含量分别为333，370和400 mg/g。对于Cr(VI)的吸附1 h左右达到平衡。 在不同粒径的PGMA高分子微球表面氨解开环反应得到的PGMA-NH2-1和PGMA-NH2微球的饱和吸附含量，分别为370和303 mg/g。吸附平衡时间均为15分钟。 上述结果均表明：本文中制备的高分子微球吸附效果较好，可以大幅提高吸附量，是具有潜力的材料，有望在今后的纯化分离中广泛应用。 关键词：PGMA；单分散；超顺磁性；铈盐引发；PEI；氨基；Cr(VI) |
| 英文摘要 | Microspheres based separation has extensive and prospective applications in many fields, such as environment-protection, bio-separation and the preparation of catalyst. However, the preparation and application of microspheres are still limited to laboratory and medical diagnostic scale rather than the application in the field of environmental protection at a large scale. There still exist lots of challenges to develop this technology in large-scale separation of Cr(VI) in waste water, e.g., developing massive production of high quality microspheres with low price; improving the content of functional groups and adsorption capacity of polymer microspheres. So, systematical study has been carried out in this paper on the preparation, surface modification and application of polymer microspheres in adsorption of Cr(VI) in waste water, and obtained the following main achievements. (1) Micron-sized monodisperse polyglycidyl methacrylate (PGMA) particles were prepared by a dispersion polymerization method in different conditions to find out the most appropriate optimal operating conditions. The size, morphology, structure and composition were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), respectively. (2) Four novel processes were developed for the preparation of superparamagnetic PGMA-NH2 microspheres, g-PGMA-NH2 microspheres by Ce(IV) initiated graft polymerization, PGMA-PEI microspheres and PGMA-NH2 microspheres of different sizes. The size, morphology, structure and composition were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometry (XRD), respectively. (3) On that basis, the adsorption properties and mechanism of superparamagnetic PGMA-NH2 and g-PGMA-NH2 microspheres by Ce(IV) initiated graft polymerization for Cr(VI) in wastewater were investigated, respectively. The main results were as follows: In a model system, the adsorption process of superparamagnetic PGMA-NH2 microspheres followed the Langmuir adsorption isotherm, and the maximum sorption capacity of were calculated to be 263.16 mg/g at 308 K, pH 4.5. The adsorption of Cr(VI) capacity were related with the different species of Cr(VI) in aqueous solution, the maximum adsorption of Cr(VI) was observed at pH 1.5. The adsorption of Cr(VI) capacity reached equilibrium within 15 min and followed pseudo second order kinetics. Both pore diffusion and film are partcipating in ruling the diffusion of Cr(VI) ions. The adsorption was a spontaneous and endothermic process with the enthalpy deviation Delta H at 9.63kJ/mol. And, the adsorption process of g-PGMA-NH2 microspheres by Ce(IV) initiated graft polymerization followed the Langmuir adsorption isotherm. The Cr(VI) adsorption results indicated that the graft polymerization of tentacle-type polymer chains on the polymer microspheres could produce the adsorption capacity as high as 500 mg/g at 308 K, pH 4.5. The adsorption of Cr(VI) capacity were related with the different species of Cr(VI) in aqueous solution, the maximum adsorption of Cr(VI) was observed at pH 1.5. The adsorption of Cr(VI) capacity reached equilibrium within 1 h. The adsorption was a spontaneous and endothermic process with the enthalpy deviation Delta H at 3.61kJ/mol. The adsorption process of PGMA-PEI600, PGMA-PEI1,800 and PGMA-PEI10,000 microspheres followed the Langmuir adsorption isotherm, and the maximum sorption capacity of were calculated to be 333, 370 and 400 mg/g at 308 K, pH 4.5. The adsorption of Cr(VI) capacity reached equilibrium within 1 h. The adsorption process of PGMA-NH2-1 and PGMA-NH2 microspheres also followed the Langmuir adsorption isotherm, and the maximum sorption capacity of were calculated to be 370 and 303 mg/g at 308 K, pH 4.5. The adsorption of Cr(VI) capacity reached equilibrium within within 15 min. The results showed that the four kinds of polymer microspheres can all improve the adsorption and have potential application in large-scale removal of Cr(VI) in aqueous solution. Keywords: PGMA, Dispersion polymerization, Superparamagnetic, Ce(IV)-initiated, PEI, Amino group, Cr(VI) |
| 语种 | 中文 |
| 公开日期 | 2013-09-25 |
| 源URL | [http://ir.ipe.ac.cn/handle/122111/1869]  |
| 专题 | 过程工程研究所_研究所（批量导入） |
| 推荐引用方式 GB/T 7714 | 李鹏飞. 氨基功能化高分子微球制备、表面修饰以及去除废水中的Cr(VI)[D]. 中国科学院研究生院. 2012. |
入库方式： OAI收割
来源：过程工程研究所
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