【作者】 邵坤；

【导师】 程先忠；

【作者基本信息】 武汉工业学院 ， 应用化学， 2011， 硕士

【摘要】 随着科学技术的发展,各种无机物和有机物不断向环境排放,造成水体严重污染,其中无机重金属元素对人类的生存环境构成严重的威胁,年初中央电视台曾报道我国有30%的大米被重金属污染,因此研究快速准确的测定环境样品中重金属元素显得尤为重要。目前,尽管仪器分析技术和方法已有较大发展,但分析对象越来越复杂,待检测组分含量越来越低,特别是基体效应和干扰物质的存在,直接影响着分析方法的灵敏度和准确度。现代仪器分析方法的发展要求分析工作者不断改进分析方法,提高测试方法的准确性、缩短分析时间、降低检测限、建立更加经济有效的检测手段。由于环境水样中的分析对象含量很低,甚至于接近仪器的检出限,直接进行测定比较困难,往往需要进行分离富集。目前采用的分离富集的方法有沉淀法、活性碳吸附法、离子交换树脂法、有机溶剂萃取、浊点萃取法以及固相萃取法。其中固相萃取分离富集技术由于具有操作简单、耗时短、试剂和样品用量少、不使用有机溶剂、对环境友好且易于与不同的检测仪器联用等特点,在样品前处理中得到了广泛的应用。而固相萃取吸附材料的选择直接影响着分析方法的灵敏度和选择性,目前使用的固相萃取吸附材料有树脂、活性碳、硅胶、泡沫塑料、碳纳米管、纳米二氧化钛、分子(离子)印迹材料以及一些生物材料,由于上述材料中有些比较昂贵,有些合成出来比较麻烦,甚至有些材料还对环境有污染,因此探讨环境友好型资源节约型的固相萃取吸附剂已经引起分析工作者的关注,由于生物材料如树皮、茶叶、海带、稻壳、壳聚糖等对重金属离子具有吸附性能,除了价格低廉、易于获取外,本身还能得到生物降解,不会对环境造成污染,因而生物材料在环境金属离子富集领域具有广阔的前景和潜力。近年来,生物材料在生物医学和污水处理领域受到广泛关注,尤其是生物材料对污染物的去除是国内外研究者感兴趣的课题,其在环境污染与防治、污水及工业污水中有毒金属离子的吸附、去除等中发挥着重要作用。由于生物材料中富含糖类、蛋白质、纤维素以及其它的生物高聚物,可能含氨基、酰胺基、酞胺基、羟基、羧基、磺酸基及巯基等多种官能团,这些官能团能够与金属离子进行络合及配位,与金属离子形成离子键或者共价键达到吸附的目的,因此,生物材料对金属离子表现出独特的选择性和吸附性能。鸡蛋膜为厚约70μm的双层结构,是一种半透性亲水生物活性膜,具有良好的透气性、保湿性以及吸附性。半透膜试验证明,鸡蛋膜能够选择性地通过乙酸、水等小分子物质,不能通过葡萄糖等大分子物质。其主要组成成分为蛋白质,近年来蛋膜(ESM)作为一种生物材料,广泛应用于如医药、食品、化妆品等领域。本文的研究目的:在文献已报道的研究基础上,主要研究了蛋膜对微量金属元素银、铜、锰的吸附性能,以及吸附条件对固相萃取效果的影响。在此基础上,将其应用于环境水样中微量金属离子的分离富集与测定。主要研究内容分为四部分,概括如下:第一章:主要综述了各种分离富集技术、固相萃取吸附材料的特点及应用。简要介绍了生物材料及其在分离富集领域应用,重点介绍了蛋膜生物材料的结构、性能以及在分离富集方面的最新研究进展,本文的立题思想及研究意义。第二章:研究了以蛋膜生物材料为固相萃取吸附剂,考察了蛋膜对微量银的吸附,利用扫描电镜和红外光谱对蛋膜进行结构表征,探讨其吸附机理,在优化的实验条件下,建立了蛋膜微柱固相萃取-石墨炉原子吸收光谱法测定微量银的方法,并将该方法成功应用于环境水样中微量银的测定。第三章:研究用蛋膜固相萃取微柱分离预富集水中的微量铜,并与原子吸收光谱法联用,实验考查了pH、流速、洗脱剂、电解质、共存离子等因素对回收率的影响。将该方法应用于环境水中,取得满意效果。第四章:在微酸性条件下,将蛋膜分离富集与电感耦合等离子体质谱法(ICP-MS)联用研究Mn(II)和Mn(VII)的吸附行为,实验探讨了影响吸附和洗脱的一些因素,并将各种影响因素进行优化,该方法成功应用于环境水样中Mn(II)和Mn(VII)的测定。更多还原

【Abstract】 The human livings standards increased substantially with the rapid development of science and technology. However, the resulting environmental pollution problems have a serious threat to the human’s circumstance. Therefore, it is very important to monitor the environmental via fast and accurately technology. Although there has greatly developed techniques and methods of instrumental analysis, the direct analysis is often very difficult even impossible for the analysis object has become more complex and the content become more and more low, in particular, the matrix effect and the presence of interfering substances. So analysts must be construct a more cost-effective detection method, such as, improve the analytic accuracy, shorten the analysis time and lower the detection limit.A variety of sample pretreatment is essential before analyzing. Solid phase extraction enrichment technology has been widely used in sample Processing for simple for its facile operation, high enrichment factor, low sample and reagent consumption, no emulsification, easy collection, environmental friendly and easy combined with different detection techniques, etc.,. The selective of solid phase adsorption material is very important to sensitivity and selectivity. Therefore, finding the right superior performance of adsorption materials has been a hot area of scientific research problem.In recent years, biological materials received extensive attention in biomedical and wastewater treatment, especially in the removal of pollutants, which has become the interest to domestic and foreign researchers. Moreover, biological materials played an important role in controlling the environmental pollution, removing the adsorption of toxic metal ions in sewage and industrial waste water. The biological materials exhibited a exciting selectivity and adsorption performance to metals ions for biosorbents cnotaining polysaccharides, lignin, protein and other biological polymers, which may be rich in amino acids, phthalic amino, hydroxyl, carboxyl, sulfonic acid groups and thiol and other functional groups. And other functional groups which could contact with the metal ions and coordination with metal ions to form ionic bonds or covalent bonds.Eggshell membrane (ESM) is a biologically active hydrophilic semipermeable double layers membrane with a thickness about 70μm. And it has a good air permeability, moisture retention and absorption. Semipermeable test proved that the acetic acid, water and other small molecules could selectively through the eggshell membrane (ESM) but glucose and other macromolecules can not. The major components of the eggshell membrane(ESM) is protein and is widely used in medicine, food, cosmetics and other fields as a biological membrane material.According to the research reported in the literature, we mainly studied on the effect of adsorption and adsorption conditions of eggshell membrane (ESM) to the metal ions silver, copper, and manganese on solid phase extraction. And applied the eggshell membrane (ESM) to separate and detect the enrichment of trace metal ions in environmental water samples. The main contents are divided into four parts, summarized as follows:Chapter I: this section introduces the characteristics of the various separation and enrichment technologies and their applications. And also Brief introduced the biological materials and their application in separation and enrichment field, the structure and performance of eggshell membrane (ESM) and the latest research progress in separation and enrichment. The idea and the meaningful of this study were also introduced in this section.Chapter II: this section we established a new method to separate and enrich silver with eggshell membrane (ESM). The solid phase extraction sorbent eggshell membrane (ESM) was coupled with graphite furnace atomic absorption spectrometry (GFAAS) and applied to analysis of actual samples. The structure of the eggshell membrane (ESM) was characterized by scanning electron microscopy(SEM) and fourier transform infrared spectroscopy(FT-IR),and their adsorption performances to silver were also studied.Chapter III: the micro-column preconcentration was coupled with the flame atomic absorption spectrometry in this section. And we also studied their adsorption behavior to copper. A new method of eggshell membrane (ESM) to enrich copper was established and applied to the actual water samples.Chapter IV: the separation and enrichment of the eggshell membrane(ESM) coupled with Inductively Coupled Plasma Mass Spectrometer (ICP-MS) to adsorb Mn (II) and Mn (VII) in the slightly acidic environmental was investigated and used to detect trace Manganese ions in water samples.更多还原