【作者】 刘建林；

【导师】 李鱼；

【作者基本信息】 华北电力大学 ， 热能工程， 2012， 博士

【摘要】 双酚A (bisphenol A, BPA)是生产聚碳酸酯、环氧树脂、阻燃剂、增塑剂以及其它塑料产品的不可或缺的有机化工原料,生产、运输和利用过程是BPA进入水体、土壤环境的主要途径,由于BPA具有与甾然雌激素雌酮(estrone, E1)、雌二醇(17β-estradiol, E2)、雌三醇(estriol, E3)以及17α-乙炔基雌二醇(17a-ethynylestradiol, EE2)类似的干扰内分泌系统的雌激素效应,在某些产品中已被许多国家列入限制使用黑名单。此外,随着畜禽养殖规模化、集约化程度不断提高,养殖废水不经处理直接排放于水体中,其中含有的甾体类雌激素E1、E2、E3以及EE2对生态环境和人体健康具有巨大的潜在危害。BPA与甾然雌激素广泛存在于环境中,并且雌激素效应明显,逐渐成为公众重视的社会问题。因此,水体环境中痕量雌激素的吸附/解吸、生物降解、迁移转化等环境行为研究已经成为环境污染控制化学领域的热点问题之一。针对多种雌激素在水环境中痕量测定方法及土壤中吸附行为的研究鲜有报道,以及为降低水体生态风险增强雌激素生物降解及吸附固定化的研究也不多见,本论文以E1、E2、EE2、E3及BPA为雌激素特征污染物,以水/土壤为环境介质为实验体系,深入系统地建立了基于分散液液微萃取技术的高效液相色谱测定水中痕量雌激素的分析方法,详细分析了雌激素在水/土壤体系中的吸附行为,探讨了葡萄糖、蛋白胨、超声波辅助作用下恶臭假单胞菌对雌激素生物降解的增强效应,并考察了添加剂对土壤吸附雌激素的固定化作用,为推动雌激素生物降解技术及防止二次污染的固定化技术提供了理论基础。本论文首先采用适宜于两液相体系、并由局部物质的量分数导出的非无序双液(non-random two liquid, NRTL)方程对雌激素在萃取相与水相中分配的摩尔分数进行关联,计算发现雌激素与[C6MIM]PF6分子间作用能大小顺序依次为EE2、BPA、E1、E2及E3。此外,雌激素在[C6MIM]PF6/水中的分配系数均高于其在传统有机萃取剂/水相中的分配系数2倍以上,[C6MIM]PF6是萃取水体中雌激素的较好选择之一。在分散液液微萃取技术的基础上,采用高效液相色谱仪(High performance liquid chromatography, HPLC)建立了水体环境中一种和多种痕量雌激素的测定方法,并从线性范围、检出限、精密度和准确度、基质效应等方面进行了评价。所建立方法的检出限均达到ppb数量级以下,且具有操作简便、费用低、环境友好、省时等优点。论文采用批实验方法考察了雌激素在土壤中的吸附动力学和热力学特性：雌激素先快吸附后慢吸附过程,在24h内达到吸附平衡；吸附热力学行为均可用Langmuir和Flundlich等温式进行描述。雌激素共存时在土壤上会发生竞争吸附行为,疏水性强的雌激素有助于疏水性弱的雌激素在土壤中的吸附。雌激素在土壤中的吸附过程中的吸附焓变ΔH<0、吸附熵变ΔS<0,表明雌激素在土壤中吸附反应为自发的、放热过程,温度升高促进雌激素的解吸,雌激素的吸附自由能△G的绝对值均小于40kJ/mol,吸附以物理吸附为主。此外,在外加碳源—葡萄糖、外加氮源—蛋白胨以及超声波辅助作用下,论文选择恶臭假单胞菌降解雌激素,研究了上述外部因素增强恶臭假单胞菌降解雌激素的作用。葡萄糖以共代谢形式增强了恶臭假单胞菌对雌激素的生物降解率,使E1、E2、EE2、E3和BPA的去除率分别增大为未加碳源时的1.6倍、1.2倍、1.2倍、2.0倍和1.3倍；蛋白胨为恶臭假单胞菌提供了氮元素及调节了适宜的pH环境,使E1、E2、EE2的去除率均达90%以上,E3去除率达60%,为未加氮源时(30%)的2.0倍,BPA的去除率达82%,为未加氮源时1.4倍；超声时间在1.0-10min内,使E1、E2、EE2和BPA的去除率提高至90%以上,而E3的去除率达近60%。最后,论文选择添加剂Mn02、腐植酸、蒙脱石及磁铁矿,进行了增强土壤吸附雌激素的作用研究。解吸实验表明四种添加剂也能够有效阻止雌激素解吸而再次进入溶液中,实现了雌激素在土壤中的固定化。对雌激素的固定化效果强弱顺序为：Mn02>磁铁矿>蒙脱石>腐植酸,但磁铁矿对E1去除率没有明显的增强作用。此外,傅里叶红外光谱从分子层面分析,可知所选添加剂增强土壤吸附雌激素的方式主要以氢键缔合、分配作用为主,同时也存在表面吸附作用。更多还原

【Abstract】 Bisphenol A (BPA) is an indispensable organic chemical for production of polycarbonate, epoxide resin, flame retardant, plasticizer and many other plastic products. BPA enters the aqueous body and soil mainly by emission during the process of manufacturing, transportation and use. BPA has been blacklisted in many countries as it has the horrible endocrine disruption effect on reproductive system, which is similar to the estrogenic effects of natural estrogens e.g. estrone (E1),17β-estradiol (E2), estriol (E3) and17α-ethynylestradiol (EE2). In addition, with the development of large-scale and intensive livestock, more and more animal farm wastewater, with E1, E2, E3and EE2together, have been discharged into surface water directly without any treatment, which poses a great potential threat to ecological environment and human health. For the commonly detection and estrogenic effect, the estrogens abovementioned have been attracted great attentions. Therefore, the adsorption/desorption, biodegradation, transportation and transformation etc. have already been become one of the most hot issues in the field of environmental pollution control chemistry.Less study on the method of determination trace level of estrogens in aqueous and adsorption behavior of estrogens in soil/water system was investigated, as well as the biodegradation and absorbed immobilization of estrogens. Hence, E1, E2, EE2, E3and BPA were chosen as typical estrogenic contaminants, the methods for determination of trace level estrogens based on dispersive liquid liquid microextraction and high performance liquid chromatography were systematically investigated, the adsorption behavior of estrogens in water/soil system was analyzed particularly, the enhancement of biodegradation of estrogens using pseudomonas putida with the help of glucose, peptone and ultrasonic assistive technologies were explored, and the absorbed immobilization of estrogens by soil spiked with additive were researched as well. The results of this study provide useful information for controlled transport of estrogens and bioremediation enhancement technology.Non-random two liquid equation was applied to correlate the experimental data in this paper, and the molecular interaction energy followed the order of EE2>BPA>E1>E2>E3. It should be noted that the partition coefficients of estrogens between [C6MIM]PF6and water phase were twice more than that between traditional extractant and water phase,[C6MIM]PF6was the alternative for extraction of estrogens from aqueous phase.Based on the dispersive liquid liquid microextraction and high performance liquid chromatography (HPLC), the analytical methods for determination of trace level estrogens in water were developed, and the established methods were evaluated in terms of the linear range, limit of detection, precision and accuracy, matrix effect and so on. The limit of detection of the methods could be below ppb, and had some advantages such as simple operation, low cost, environmental friendly and saving-time.The adsorption kinetics and thermodynamics of estrogens in soil were discussed using batch experiment. Adsorption of estrogens on soil consisted of two processes of quick adsorption and slow adsorption, and reached a state of equilibrium in24h. Both Langmuir and Flundlich isotherms could describe the adsorption thermodynamic behavior. The experimental results showed that competitive adsorption was occurred when coexistence of estrogens and higher hydrophobicity of estrogen could promote lower hydrophobicity of estrogen adsorption on soil. The negative values of adsorption enthalpy and sorption entropy of estrogens indicated that the overall adsorption processes are exothermic in nature. The modulus of free energy of adsorption value is less than40kJ/mol, which implied that the adsorption mechanisms of estrogens are dominated by physical adsorption.Additionally, under the external carbon source-glucose, nitrogen addition-peptone, and ultrasonic assistive technologies conditions, pseudomonas putida was selected to degrade estrogens in the paper. The enhancement effects of factors mentioned above on the biodegradation were studied. Glucose prompted the biodegradation efficiency in the form of cometabolic degradation, and the removal rates of E1, E2, EE2, E3and BPA were1.6times,1.2times,1.2times,2.0times and1.3times of that without addition of glucose; peptone provided nitrogen and suitable pH for micrograms, and increased the removal rates of E1, E2, EE2to above90%, the removal rates of E3and BPA were more than60%and82%, which were2.0times and1.4times of that without addition of peptone, respectively. The removal rates of E1, E2, EE2and BPA increased more than90%, and the E3increased to60%in10.0min with the help of ultrasonic assistive technology.Finally, MnO2, humic acids, montmorillonite and Fe3O4were employed to enhance the estrogens adsorption onto the soil. The experimental results of desorption showed the all of the additives could obviously reduce the desorption quantity and realize the immobilization of estrogens in soil, keeping the water body free from pollution. The immobilized results followed the order of MnO2> Fe3O4> montmorillonite> humic acids; however, the immobilization of E1by Fe3O4was not significant. Moreover, from molecular response using FTIR spectroscopy, it can be known that the enhanced effect of the additive on the estrogens adsorbed onto soil were contributed mainly by the hydrogen bonding association, partition, and surface adsorption as well.更多还原