双酚A分子印迹介孔有机硅材料的制备和表征

发布时间：2018-06-24 03:49

本文选题：双酚A + 介孔材料　；参考：《北京理工大学》2015年硕士论文

【摘要】：分子印迹聚合物具有选择性高、稳定性好、抗恶劣环境能力强等特点,广泛应用于分离分析、固相萃取、传感器、药物检测等领域。一般方法制得的印迹聚合物结合位点和印迹空穴嵌入较深,吸附动力学时间长,而介孔硅材料结构坚硬,具有比表面积大、空隙容积高、热稳定性好、孔径大小可调、易功能化的特点,非常适合作为印迹基质以形成表面印迹位点,可以解决传统分子印迹方法存在的一些不足。本文综述了分子印迹聚合物的合成方法并分析了各种方法存在的优缺点以及硅基印迹基体的发展过程。介绍了介孔材料MCM-41和SBA-15的合成方法、表征方法及应用,提出了论文的选题依据,研究意义及研究内容。通过优化合成条件制备了两种不同的介孔材料MCM-41和SBA-15作为分子印迹基体,其中MCM-41以十六烷基三甲基溴化铵作为模板剂,在弱碱性环境中,以正硅酸乙酯为硅源,加入乙醇,氨水调节pH,经过水热老化的过程制得。SBA-15的合成以P123三嵌段共聚物作为模板剂,以正硅酸乙酯作为硅源,在酸性条件下通过水热合成的方法制得,两种介孔材料都通过高温煅烧的方法去除模板剂。对介孔材料分别进行了红外光谱、X射线衍射、SEM表征,然后通过对介孔材料进行氨基化修饰使其能够形成与模板分子结合的位点,再与模板分子结合制备分子印迹介孔有机硅材料,并通过对两种不同基体制备的印迹材料进行动力学,吸附等温线,吸附选择性,循环吸附实验测试。MCM-41基分子印迹介孔硅材料对双酚A的吸附50 min内达到吸附平衡,吸附选择性实验表明MIP的吸附量远大于NIP的吸附量,并且在有类似物竞争时,对模板分子具有特异性吸附性能。循环吸附实验经四次洗脱-吸附-洗脱后吸附量为原来的60%左右,有一定的循环利用性。SBA-15基分子印迹介孔硅材料的吸附平衡约20 min即可达到吸附平衡,与传统的分子印迹聚合物相比速率有了较大的提高,对模板分子的吸附有较高的选择性。四次洗脱-吸附-洗脱后吸附量为原来的50%左右,也保持了一定的循环使用性。SBA-15基印迹介孔硅材料对实际样品的应用具有潜在的价值。比较了两种不同的介孔基印迹聚合物的吸附性能,对印迹聚合物的吸附动力学,吸附等温线,吸附选择性以及循环利用率进行了比较。SBA-15基印迹聚合物的吸附速率和吸附量都远远大于MCM-41基印迹聚合物,循环利用率略低于MCM-41基印迹聚合物。这与基体自身的孔结构有很大的关联。使用SBA-15-MIP对水样品进行双酚A加标回收实验,实验结果对双酚A的加标回收率在92.8%~99%%之间,结果表明SBA-15-MIP对样品中双酚的富集有效。制备的SBA-15基印迹聚合物对双酚A的吸附在20 min以内达到吸附平衡,较快的吸附速率以及较高的吸附量使得SBA-15基印迹聚合物在双酚A的富集方面具有较好的实际应用价值。
[Abstract]:Molecularly imprinted polymers (MIPs) are widely used in separation and analysis, solid phase extraction, sensors, drug detection and so on. The imprinted polymer has deep binding sites and imprinted holes, and the adsorption kinetics is long. The mesoporous silicon materials have hard structure, large specific surface area, high void volume, good thermal stability and adjustable pore size. The feature of easy functionalization is very suitable as imprinting substrate to form surface imprinting sites, which can solve some shortcomings of traditional molecular imprinting methods. In this paper, the synthetic methods of molecularly imprinted polymers are reviewed, and the advantages and disadvantages of these methods and the development of silicon-based imprinted matrix are analyzed. The synthesis, characterization and application of mesoporous materials MCM-41 and SBA-15 were introduced. Two kinds of mesoporous materials MCM-41 and SBA-15 were prepared by optimizing the synthesis conditions. MCM-41 used cetyltrimethylammonium bromide as template, ethyl orthosilicate as silicon source, and ethanol was added into MCM-41. In the process of hydrothermal aging, the synthesis of .SBA-15 was prepared by adjusting pH with ammonia water, using P123 triblock copolymers as template and ethyl orthosilicate as silicon source, and was synthesized by hydrothermal method under acidic conditions. Both mesoporous materials were calcined at high temperature to remove the template. The mesoporous materials were characterized by FTIR X-ray diffraction (XRD) SEM, and then modified by amination of mesoporous materials to form sites binding to template molecules. Then the molecular imprinted mesoporous organosilicon materials were prepared by binding with template molecules. The adsorption isotherms and selectivity of the imprinted materials prepared by two different substrates were carried out. The adsorption equilibrium of BPA on MCM-41 based molecularly imprinted mesoporous silicon material was observed in 50 min. The adsorption selectivity experiment showed that the adsorption capacity of MIP was much larger than that of nip, and when there was competition between MCM-41 and MCM-41, the adsorption capacity of MIP was much higher than that of nip. The template molecules have specific adsorption properties. After four times of elution, the adsorption capacity was about 60%, and the adsorption equilibrium of molecular imprinted mesoporous silicon based on SBA-15 was about 20 min. Compared with the traditional molecularly imprinted polymers, the adsorption rate of the template molecules is higher than that of the traditional imprinted polymers. The adsorption capacity of four elution adsorption-elution is about 50%, and the reusability of SBA-15 based imprinted mesoporous silicon material has potential value for the application of practical samples. The adsorption properties, adsorption kinetics and adsorption isotherm of two different mesoporous imprinted polymers were compared. The adsorption rate and adsorption capacity of SBA-15 group imprinted polymer were much higher than that of MCM-41 group imprinted polymer, and the cyclic utilization ratio was slightly lower than that of MCM-41 group imprinted polymer. This is closely related to the pore structure of the matrix itself. SBA-15-MIP was used for the recovery of bisphenol A in water samples. The results showed that the recoveries of bisphenol A were between 92.8% and 99%. The results showed that SBA-15-MIP was effective in the enrichment of bisphenol in water samples. The adsorption equilibrium of SBA-15-group imprinted polymer for bisphenol A was achieved within 20 min. The higher adsorption rate and higher adsorption amount made SBA-15-base imprinted polymer have good practical application value in the enrichment of bisphenol A.
【学位授予单位】：北京理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O631.3;TB383.4

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