【作者】 安富强；

【导师】 高保娇；

【作者基本信息】 中北大学 ， 军事化学与烟火技术， 2010， 博士

【摘要】 重金属离子废水及含酚废水是造成水污染的主要来源,对人类社会已经造成了很大的危害。因此,通过分子设计,制备既能够高效地处理废水中的污染物,又能够有效地分离和回收有用物质的高性能(高结合容量、高选择性)材料,具有重要的环境保护与资源再利用价值。本课题首先制备了两种接枝型复合材料并充分研究了它们对重金属离子及酚类物质的吸附性能与吸附机理。在此基础上,本课题在国际范围内首次提出并建立了一种新型的表面分子印迹技术,在硅胶表面实施了重金属离子及酚类物质的分子(离子)印迹,制备了三类高性能的分子(离子)表面印迹材料,充分研究了它们对模板分子(离子)的结合性能与识别机理。所制备的分子(离子)表面印迹材料对重金属离子以及酚类物质等环境污染物具有高效的去除能力。本课题的研究结果在环境保护与治理领域具有重要的科学意义与应用价值。通过γ-氯丙基三甲氧基硅烷的媒介,采用“接枝到”("graft to")的方法将功能大分子聚乙烯亚胺(polyethyleneimine, PEI)接枝到硅胶微粒表面,制备了接枝型复合材料PEI/SiO2；考察研究了PEI/SiO2对Cu2+、Cd2+、Pb2+、Zn2+、Cr3+等重金属离子的吸附性能与吸附机理。实验结果表明,PEI/SiO2对Cu2+、Cd2+、Pb2+、Zn2+、Cr3+等重金属离子具有强的螯合吸附能力。PEI/SO2对重金属离子的吸附属于单分子层化学吸附,吸附行为符合Langmuir吸附模型。吸附容量受pH以及温度的影响很大,在重金属离子不发生水解的pH值范围内,随着pH的增大,吸附容量增高；吸附容量随温度升高而增大,充分显示出化学吸附的特征。在上述研究基础上,以Cu2+、Cd2+、Pb2+、Cr3+为模板离子,环氧氯丙烷为交联剂,对化学接枝在硅胶微粒表面的功能大分子PEI进行了重金属离子印迹,制备了四种重金属离子的表面印迹材料IIP-PEI/SiO2；考察研究了IIP-PEI/SiO2对模板离子的结合性能与识别选择性。实验结果表明,IIP-PEI/SiO2对模板离子具有优良的结合亲和性与特异的离子识别选择性。与印迹之前的接枝型复合材料PEI/SiO2相比,重金属离子印迹材料IIP-PEI/SiO2对模板离子的选择性系数提高了14-60倍。离子印迹材料IIP-PEI/SiO2还具有良好的脱附性能与重复使用性能,用0.1mol·L-1的盐酸就可以实现重金属离子的脱附,而且重复使用性能好,使用10次以后结合容量基本不变。对于接枝型复合材料PEI/SiO2,还深入考察研究了它对苯酚及对硝基苯酚等酚类物质的吸附性能与吸附机理。实验结果表明,凭借氢键相互作用与静电相互作用的协同,PEI/SiO2对酚类物质具有很强的吸附作用,吸附属于单分子层的物理吸附,吸附行为符合Freundlich吸附模型。吸附容量受pH以及温度的影响很大,吸附容量随介质pH的增大呈现先增大后降低的规律,在pH为7时,吸附容量最大；吸附容量随温度升高而降低,显示出物理吸附的特点。在上述研究的基础上,分别以苯酚及对硝基苯酚为模板分子,乙二醇二缩水甘油醚为交联剂,对化学接枝在硅胶微粒表面的功能大分子PEI进行了苯酚及对硝基苯酚分子印迹,制备了苯酚及对硝基苯酚分子的表面印迹材料MIP-PEI/SiO2。考察研究了两种分子印迹材料MIP-PEI/SiO2对模板分子的结合性能与识别选择性。实验结果表明,两种印迹材料MIP-PEI/SiO2对模板分子具有优良的结合亲和性与特异的分子识别选择性。与印迹之前的接枝型复合材料PEI/SiO2相比,分子印迹材料MIP-PEI/SiO2对模板分子的选择性系数提高了11-40倍。MIP-PEI/SiO2还具有良好的脱附性能与重复使用性能,用0.1mol·L-1的盐酸就可以实现苯酚及对硝基苯酚的脱附,使用10次以后结合容量基本不变。通过3-(甲基丙烯酰氧)丙基三甲氧基硅烷的媒介,采用“接枝于”("graft from")的方法将功能大分子聚甲基丙烯酸(polymethylacrylic acid, PMAA)接枝到硅胶微粒表面,制备了接枝型复合材料PMAA/SiO2；考察研究了PMAA/SiO2对苯酚的吸附性能与吸附机理。凭借氢键相互作用,PMAA/SiO2对苯酚具有强的吸附作用,吸附属于单分子层的物理吸附,吸附行为符合Freundlich吸附模型。吸附容量受pH以及温度的影响很大,吸附容量随介质pH的增大而降低；吸附容量随温度升高而减小,显示出物理吸附的特点。在上述研究的基础上,以苯酚为模板分子,乙二醇二缩水甘油醚为交联剂,对化学接枝在硅胶微粒表面的功能大分子PMAA进行了苯酚分子印迹,制备了苯酚分子的表面印迹材料MIP-PMAA/SiO2。考察研究了MIP-PMAA/SiO2对苯酚的结合性能与识别选择性。实验结果表明,MIP-PMAA/SiO2对苯酚具有优良的结合亲和性与特异的分子识别选择性。与印迹之前的接枝型复合材料PMAA/SiO2相比,苯酚分子印迹材料MIP-PMAA/SiO2对苯酚的选择性系数提高了22-25倍。MIP-PMAA/SiO2具有良好的脱附性能与重复使用性能,用0.01mol·L-1的氢氧化钠溶液就可以实现苯酚的脱附,使用10次以后结合容量基本不变。更多还原

【Abstract】 Wastewater containing heavy-metal ions and phenolic compound are primary source of water pollution, and has been caused great endangerment for the human society. Therefore, via the molecule design, preparing the high-performance material, which can be used effectively not only for treating pollutant in wastewater but also for separating and reclaiming pollutant, have important environment protection and resource recycling value. Two kinds of grafted composited materials were prepared and its adsorption abilities and mechanism towards heavy-metal ions and phenolic compound were researched. On the base of this, noval surface molecular imprinting technology was founded firstly in the international range. Three kinds of high-performance heavy-metal ion and phenolic compound-imprinted materials were prepared and its binding abilities and recongnizing mechanism towards template were researched. The prepared molecularly imprinted materials possess effective removing ability to heavy-metal ions and phenolic compound. The investigation results possess important scientific significance and applied value in environment protection and treatment.Functional macromolecule polyethyleneimine (PEI) was grafted onto the surface of silica gel particles with the "graft to" method using y-chloropropyl trimethoxy silane as coupling agent, and the grafted composited material PEI/SiO2 was prepared. The adsorption abilities and mechanism of PEI/SiO2 towards Cu2+, Cd2+, Pb2+, Zn2+, and Cr3+ ions were studied. The experiment results showed that PEI/SiO2 possesses very strong chelating adsorption ability for Cu2+, Cd2+, Pb2+, Zn2+ and Cr3+ ions. The adsorption is chemical adsorption with monomolecular layer and accord with the Langmuir adsorption model. The pH and temperature have great influence on the adsorption capacity. The adsorption capacity increases with the decreases of pH before the heavy-metal ions were hydrolyzed. The adsorpyion capacity increases with the increases of temperature and this displayed the character of chemical adsorption. The functional macromolecules PEI on the surface of silica gel particles were ionic imprinted using Cu2+, Cd2+, Pb2+, Cr3+ as template ion and epichlorohydrin as crosslinking reagent and four surface ion-imprinted materials IIP-PEI/SiO2 were prepared. The binding ability and recognizing selectivity of IIP-PEI/SiO2 towards template ion were researched. The experiment results showed that IIP-PEI/SiO2 possesses very excellent binding affine and recognizing selectivity towards template ion. The selectivity coefficient of IIP-PEI/SiO2 towards template ion was 14-60 times than that of PEI/SiO2. IIP-PEI/SiO2 possesses well elute and reuse property. The adsorbed metal ions could be eluted easily from IIP-PEI/SiO2 using 0.1mol·L-1 hydrochloric acid as eluent, and the binding capacity of IIP-PEI/SiO2 remains unchanged nearly after 10 times use.The adsorption abilities and mechanism of PEI/SiO2 towards phenol and p-nitrophenol were also studied. The experiment results showed that PEI/SiO2 possesses very strong adsorption ability for phenol and p-nitrophenol by way of hydrogen bond interaction and electrostatic interaction. The adsorption is physical adsorption with monomolecular layer and accord with the Freundlich adsorption model. The pH and temperature have great influence on the adsorption capacity. The adsorption capacity was the highest at pH of 7. The adsorpyion capacity increases with the decreases of temperature and this displayed the character of physical adsorption.The functional macromolecules PEI on the surface of silica gel particles were molecular imprinted using phenol and p-nitrophenol as template molecule and ethylene glycol diglycidyl ether as crosslinking reagent and two surface molecular-imprinted materials MIP-PEI/SiO2 were prepared. The binding ability and recognizing selectivity of MIP-PEI/SiO2 towards template molecule were researched. The experiment results showed that MIP-PEI/SiO2 possesses very excellent binding affine and recognizing selectivity towards template molecule. The selectivity coefficient of MIP-PEI/SiO2 towards template molecule was 11-40 times than that of PEI/SiO2. MIP-PEI/SiO2 possesses well elute and reuse property. The adsorbed phenol and p-nitrophenol could be eluted easily from MIP-PEI/SiO2 using 0.1mol·L-1 hydrochloric acid as eluent, and the binding capacity of MIP-PEI/SiO2 remains unchanged nearly after 10 times use.Functional macromolecule polymethylacrylic acid (PMAA) was grafted onto the surface of silica gel particles with the "graft from" method using 3-methacryloxypropyl trimethoxysilane as coupling reagent, and the grafted composited material PMAA/SiO2 was prepared. The adsorption abilities and mechanism of PMAA/SiO2 towards phenol were studied. The experiment results showed that PMAA/SiO2 possessess strong adsorption ability for phenol by way of hydrogen bond interaction. The adsorption is physical adsorption with monomolecular layer and accord with the Freundlich adsorption model. The pH and temperature have great influence on the adsorption capacity. The adsorption capacity decreases with the increases of pH. The adsorpyion capacity increases with the decreases of temperature and this displayed the character of physical adsorption.The functional macromolecules PMAA on the surface of silica gel particles were molecular imprinted using phenol as template molecule and ethylene glycol diglycidyl ether as crosslinking reagent, and the phenol suface molecular-imprinted material MIP-PMAA/SiO2 was prepared. The binding ability and recognizing selectivity of MIP-PMAA/SiO2 towards phenol were researched. The experiment results show that the MIP-PMAA/SiO2 possesses very excellent binding affine and recognizing selectivity towards phenol. The binding capcity remains unchanged nearly. The selectivity coefficient of MIP-PMAA/SiO2 towards phenol was 22-25 times than that of PMAA/SiO2. MIP-PMAA/SiO2 possesses well elute and reuse property. The adsorbed phenol could be eluted easily from MIP-PMAA/SiO2 using 0.01mol·L-1 sodium hydroxide as eluent, and the binding capacity of MIP-PMAA/SiO2 remains unchanged nearly after 10 times use.更多还原