【作者】 黄忠平；

【导师】 朱岩； 郭伟强；

【作者基本信息】 浙江大学 ， 化学， 2014， 博士

【摘要】 随着科技的迅速发展,离子色谱作为色谱分析的重要分支,已经被广泛应用于环境监测、电力和能源行业、电子行业、食品及饮料行业、化学工业、制药行业和生命科学等领域。与其他色谱分支一样,色谱柱作为各目标分析物的分离场所,是整个分离系统的核心,更是色谱工作者的研究热点。同时随着离子色谱应用领域的逐渐拓展,所面临样品的多样性和复杂性不断增加,对样品前处理方法提出了更高的要求。本文开发了表面超支化接枝型及碳纳米管附聚型两类阴离子交换色谱固定相的制备方法,并将其应用于离子色谱柱切换系统在线样品前处理研究中。第一部分：第一章简单介绍了离子色谱的发展、分类及其主要应用领域,着重介绍了离子交换色谱固定相的研究进展,并对各类固定相制备方法的优缺点进行了总结。随后综述了碳纳米管在色谱固定相制备中的应用,为碳纳米管应用于离子色谱固定相的制备提供了依据。第二部分：第二章以聚苯乙烯-二乙烯基苯微球为基质,利用甲胺及1,4-丁二醇二环氧甘油醚的循环缩聚反应在微球表面接枝超支化阴离子交换基团,制备了不同交换容量的阴离子色谱固定相。通过扫描电镜、元素分析、突跃曲线、无机离子色谱分离等检测方法表征了填料的表面形貌、元素含量、交换容量及色谱分离性能,最后将自制色谱柱应用于自来水中无机阴离子的测定中。第三章将自制的超支化修饰聚苯乙烯-二乙烯基苯色谱柱应用于单泵柱切换同时测定强保留与弱保留离子中,优化了色谱条件及柱切换时间,并实现了强保留离子先于弱保留离子被检出分析。同时该离子色谱柱切换技术被成功应用于聚维酮碘溶液中碘与碘酸根离子的同时测定。第四章利用自制的超支化修饰聚苯乙烯-二乙烯基苯色谱柱,实现了单泵柱切换技术测定高盐基质中痕量阴离子。利用抑制器能将淋洗液中和成水的特点,将从抑制器中流出的离子进行富集和二次分析。优化了色谱条件及柱切换时间,完成了加碘食盐中痕量碘酸根的测定。第三部分：第五章建立了一种季铵化碳纳米管的制备方法。将多壁碳纳米管进行酸化处理后,利用甲胺及1,4-丁二醇二环氧甘油醚的缩聚反应,可得到季铵化修饰的多壁碳纳米管。通过红外光谱、热重分析、扫描电镜等表征方法,考察了多壁碳纳米管表面的功能基团及形貌。季铵化修饰后的碳纳米管含有大量亲水基团及正电荷,显著提高了碳纳米管的水溶液分散性。第六章建立了一种碳纳米管附聚型离子色谱固定相的制备方法。利用静电相互作用将季铵化修饰多壁碳纳米管附聚于磺化聚苯乙烯-二乙烯基苯微球表面,制备成阴离子交换色谱固定相。考察了碳纳米管附聚后基质微球的表面形貌及色谱性能,并将固定相应用于含磷阴离子的分析中。更多还原

【Abstract】 As the rapid development of technology, ion chromatography (IC), an important branch of chromatography, has been widely used in the fields of environmental monitoring, power and energy industry, electronic industry, food and beverage industry, chemical industry, pharmaceutical industry and bioscience, etc. Same as other chromatographic techniques, columns are the heart of IC for it is the place where interaction between the stationary phase and analyte occurs. Therefore, study on preparation of novel ion chromatographic stationary phases has attracted the interest of scientists. Additionally, the varieties and complexities of samples are increasing as well as the requirements of sample pretreatment, with the spread of IC application. This dissertation focuses on preparation and application of anion exchange stationary phases with hyperbranched polymers or electrostatic agglomerated carbon nanotubes on polymeric substrates for ion chromatography. Moreover, the homemade columns are applied in on-line sample pretreatment column-switching for ion chromatography.Part Ⅰ:In chapter one, it briefly introduced the development history, classification and main application fields of IC, and focused on the research progress of ion-exchange stationary phases as well as the summary of advantages and disadvantages of various methods of preparing stationary phases. Then, preparation of novel chromatographic stationary phases with carbon nanotubes were reviewed, as the foundation of preparing stationary phases with carbon nanotubes for IC.Part Ⅱ:In chapter two, a novel anion exchange stationary phase with hyperbranched polymers grafted on polystyrene-divinylbenzene (PS-DVB) substrates for IC was prepared. The modified PS-DVB was based on the polycondensation reaction between1,4-butanediol diglycidyl ether (BDDE) and methylamine (MA) to get hyperbranched anion-exchange groups. Controlled synthesis allowed obtaining stationary phase with defined number of bonded layers and appropriate anion-exchange capacity. Several methods were utilized to characterize the stationary phase, such as the scanning electron microscope (SEM), elemental analysis, breakthrough curves and the separation of common inorganic anions in order to study the surface morphology, elemental contents, exchange capacity and chromatographic separation performance. Finally, Tap water was chosen to be analyzed without dilution on the homemade column.In chapter three, a simple ion chromatographic method for simultaneous detection of anions with weak retention and strong retention in a single running was proposed, with columns packed with homemade functionalized polystyrene-divinylbenzene (PS-DVB) resins and column-switching technique. The chromatographic conditions and column switching time were optimized. With the column-switching technique, anions with strong retention could be eluted off the column and detected prior to anions with weak retention. Anions in povidone iodine solution were analyzed by the column-switching IC system.In chapter four, a single pump cycling-column-switching technique has been developed for the analysis of trace anions in high salt matrices, with the homemade functionalized polystyrene-divinylbenzene (PS-DVB) columns. Anions could be concentrated and analyzed twice in homemade columns after eluent passing through the suppressor, for the eluent of KOH was converted into water in suppressor, which having rather low eluting power for the concentrator column. The chromatographic conditions and column switching time were optimized. Iodate in iodized edible salt was analyzed by the column-switching IC system.Part Ⅲ:In chapter five, it described a method of covalent functionalization of multi-walled carbon nanotubes (MWCNTs) with quaternary ammonium groups. MWCNTs were easily quaternized with a defined number of bonded layers and desirable positive charge by a multi-step synthesis after acid treatment, using methylamine and1,4-butanediol diglycidyl ether as monomers to build a branching polymer that has quaternary ammonium groups. Functionalization of MWCNTs was characterized by techniques that include Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TGA) and SEM. The dispersion of MWCNTs in deionized water was enhanced after the grafting of cationic polyelectrolytes on them, which was in agreement with the positive charge at any pH value.In chapter six, an approach for fabrication of core-shell composite beads was described, with polystyrene-divinylbenzene (PS-DVB) as the core and multi-walled carbon nanotubes (MWCNTs) as the shell through electrostatic attraction-induced self-assembly. Quaternized multi-walled carbon nanotubes (Q-MWCNTs) were electrostatically adsorbed onto the surface of sulfonated PS-DVB beads to generate the anion exchanger, which were confirmed by FTIR and SEM. The stationary phase was rigid, chemically stable and showed good ion-exchange characteristics, and the analysis of phosphorus-containing anions was performed on the stationary phase.更多还原