太湖流域饮用水中微量有机污染物高级氧化技术研究

发布时间：2018-05-10 22:21

本文选题：共存体系 + 类固醇雌激素　；参考：《东南大学》2015年硕士论文

【摘要】：水中新兴有机污染物是饮用水安全的重大隐患。在我国诸多水体中均不同程度地检测出了药品、个人护理品和内分泌干扰物。这些有机污染物能够在自然环境中不断积累、富集,进而通过饮用水和食物链的富集作用对人体和其他生物造成严重的危害,如使生物体内分泌失调、致癌、致畸和致突变等。并且,这些污染物往往难以通过常规水处理工艺进行去除。在现有的有机物处理技术中,高级氧化工艺因具有氧化速率快、反应条件温和、适用范围广和无二次污染等特点得到了大量的研究和应用。本文考察基于臭氧和紫外的高级氧化工艺对共存体系中类固醇雌激素和磺胺类抗生素去除特性,并对降解机理、影响因素、降解途径、生物毒性等做了详尽的研究。类固醇雌激素和磺胺类抗生素在O3和UV体系中均有很好的去除效果,O3去除磺胺类物质主要依靠O3分子直接氧化作用,而氧化类固醇雌激素时,-OH的间接氧化作用不可被忽略；三种磺胺类抗生素均具有很好的光解活性,能够被UV单独去除,类固醇雌激素(除了雌酮)紫外光解活性较差；UV/H2O2相比单独UV和O3,更能够使目标污染物彻底矿化；共存反应体系中类固醇雌激素、磺胺类抗生素的降解均符合一级反应动力学模型。高级氧化工艺降解影响因素分析：增加臭氧浓度或紫外光强能够强化有机污染物的去除,而提高污染物的初始浓度则会导致降解效能下降,这本质上是投配比(即臭氧或光量子投量与有机污染物的浓度比)决定了有机污染物的降解效能;对于O3工艺,溶液的pH值能通过两方面影响有机污染的降解效能：一是pH的改变能够影响O3的直接反应和间接反应的贡献大小,二是pH的改变能够影响有机污染物的离解状态从而影响其与臭氧分子的反应活性；对于UV/H2O2工艺,pH值主要通过影响有机物的离解状态进而影响其光解活性；阴离子对降解过程的影响与氧化体系和氧化机理有很大关系,方面作为·OH捕获剂而起抑制作用,另一方面作为O3的稳定剂而促进臭氧氧化反应的进行,或是在UV辐射下能够产生·OH从而促进UV/H2O2氧化工艺;腐殖酸在两类氧化体系中均起到抑制效果。采用GC/MS手段鉴别类固醇雌激素降解中间产物发现：高级氧化工艺去除类固醇雌激素,既可能攻击苯环上的氢原子,也可能攻击环烃中碳原子上的氢原子,从而产生羟基,并被进一步氧化为羰基和羧酸,同时分子结构中的羟基也容易被氧化为羰基,进而发生断链和开环,最终被彻底矿化。采用LC/MS/MS手段鉴别磺胺类物质降解中间产物发现：O3和UV处理磺胺类抗生素的过程中产生了大量的中间产物,而这些产物部分保留或完全保留了母体分子中的某些官能团结构；O3氧化产物主要包括羟基化产物、氨基氧化为硝基产物、氨基被羟基取代产物、氮硫键断裂产物以及甲基氧化成羧酸产物；单独UV和UV/H2O2降解产物相似,主要包括羟基化产物、氨基氧化为硝基产物、磺酰基脱除产物、氮硫键断裂产物、碳碳双键加成产物以及杂环开环产物。采用酵母菌雌激素筛选测试(YES)考察类固醇雌激素降解过程雌激素活性变化发现：各氧化工艺能够有效降低雌激素活性,然而由于降解产物仍具有一定的雌激素活性,从而导致雌激素活性的降低较雌激素本身浓度的下降表现出滞后性。采用小球藻急性毒性试验考察磺胺类物质降解过程毒性变化发现：臭氧氧化磺胺类抗生素过程中产生的某些中间产物具有比本体物质更强的生物毒性,且随着反应进行中间产物还具有抗臭氧氧化特性,其不能够被臭氧进一步降解；虽然UV/H2O2降解过程其毒性也会增强,然而随着本底物质逐步矿化去除,反应最终生物毒性也可被去除。
[Abstract]:The emerging organic pollutants in water are a major hidden danger in the safety of drinking water. Drugs, personal care products and endocrine disruptors are detected in various water bodies of our country. These organic pollutants can accumulate and enrich in the natural environment, and then build up the human body and other organisms through the enrichment of drinking water and food chain. Serious hazards, such as endocrine disorders, carcinogenesis, teratogenicity and mutagenesis, are often difficult to remove by conventional water treatment processes. In the existing organic treatment technology, the advanced oxidation process has the characteristics of rapid oxidation rate, mild reaction strip, wide application and no two pollution. The removal characteristics of steroid estrogens and sulfonamides in the coexisting system were investigated by advanced oxidation processes based on ozone and ultraviolet, and the degradation mechanism, influencing factors, degradation pathways and biological toxicity were studied in detail. Steroid estrogen and sulfonamides were both in the O3 and UV systems. With good removal effect, O3 removal of sulfonamides mainly depends on the direct oxidation of O3 molecules, while the indirect oxidation of -OH can not be ignored when the steroid estrogen is oxidized; the three sulfonamides have good photodissociation activity, can be removed by UV alone, and the UV photodissociation activity of the estrogen like estrogen (except Estrone) is poor; U Compared with individual UV and O3, the target pollutants can be completely mineralized, and the degradation of steroid estrogens and sulfonamides in the coexisting reaction system conforms to the first order kinetic model. The analysis of the factors affecting the degradation of the advanced oxidation process is that the increase of ozone concentration or ultraviolet light intensity can strengthen the removal of organic pollutants and improve pollution. The initial concentration of the dye leads to degradation efficiency, which essentially determines the degradation efficiency of organic pollutants; for the O3 process, the pH value of the solution can affect the degradation efficiency of organic pollution by two aspects: first, the change of pH can affect the direct O3. The contribution of the reaction and the indirect reaction, two is that the change of pH can affect the dissociation state of organic pollutants and the reactivity of the ozone molecules. For the UV/H2O2 process, the pH value is mainly influenced by the dissociation state of the organic matter and the photodissociation activity, the influence of the anion on the degradation process and the oxidation system and oxidation. There is a great relationship between the mechanism and the inhibition effect as the OH capture agent. On the other hand, as a stabilizer for O3, it promotes the ozonation reaction, or is able to produce OH under UV radiation to promote the UV/H2O2 oxidation process; humic acid plays an inhibitory effect in the two type of oxidation system. The use of GC/MS to identify steroid estrogens The degradation intermediates found that the advanced oxidation process removes the steroid estrogens, which may attack hydrogen atoms on the benzene ring or attack hydrogen atoms on the carbon atoms in the cyclic hydrocarbons, thus producing hydroxyl groups and further oxidizing to carbonyl and carboxylic acids, and the hydroxyl groups in the molecular structure are easily oxidized to carbonyl groups and then chain and open. The ring was eventually mineralized. The intermediate products of sulfonamides degradation were identified by LC/MS/MS, and it was found that O3 and UV produced a large number of intermediate products in the process of treating sulfonamides, which retained or completely retained some functional unity in the mother molecule, and the O3 oxidation products mainly included hydroxylation products. Amino oxidation is nitro product, amino group is substituted by hydroxyl group, nitrogen sulfur bond fracture product and methyl oxidation product of carboxylic acid. The degradation products of UV and UV/H2O2 are similar, mainly including hydroxylation products, amino oxidation to nitro products, sulfonyl removal products, nitrogen sulfur bond fracture products, carbon carbon double bond addition products and heterocyclic ring opening products. The changes of estrogen activity in the steroid estrogen degradation process were examined by yeast estrogen screening test (YES). The oxidation process could effectively reduce the estrogen activity, but the degradation product still had a certain estrogen activity, which led to the decrease of estrogen activity and the decrease of the estrogen concentration. In the acute toxicity test of Chlorella, the toxicity of the sulfonamides degradation process was investigated. It was found that some intermediate products produced by the ozone oxidizing sulfonamides have more biotoxicity than the bulk substances, and the intermediate products also have the characteristics of ozone oxidation and can not be further reduced by ozone. Although the toxicity of UV/H2O2 degradation is enhanced, the final biological toxicity can also be removed with the gradual removal of background matter.

【学位授予单位】：东南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU991.2

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