本文選題：Fe@Fe_2O_3納米線　切入點：溴酸鹽　出處：《華中師范大學》2015年碩士論文

【摘要】：經(jīng)濟的飛速發(fā)展改善了人們的生活,但也破壞了我們的生存環(huán)境。尋求高效綠色的環(huán)境治理手段已成為環(huán)保工作者關注的焦點。鐵是一類活潑的過渡金屬元素,在地殼中含量豐富。在眾多的環(huán)境治理途徑中,鐵作為一類環(huán)境友好的材料引起了環(huán)保工作者的廣泛關注。零價鐵具有較強的還原性,能直接還原去除環(huán)境中的污染物,使污染物危害或毒性減弱；同時,零價鐵還能活化空氣中的氧氣,通過產(chǎn)生活性氧物種氧化降解甚至完全礦化去除有機污染物。本論文合成了核殼結(jié)構鐵納米線材料,研究了這種特殊結(jié)構納米零價鐵去除水中典型污染物溴酸鹽和阿特拉津的效率和機理。論文的主要研究內(nèi)容如下：1.溴酸鹽是高級氧化技術特別是臭氧氧化技術消毒飲用水過程產(chǎn)生的消毒副產(chǎn)物,它被國際癌癥組織定義為一種2B級的潛在致癌物質(zhì)。本論文討論了在中性pH條件下核殼結(jié)構Fe@Fe2O3納米線對溴酸鹽的去除,并探究了反應過程中間產(chǎn)物以及體系中亞鐵的作用；另外還探究了溶解氧對于溴酸鹽去除的影響。結(jié)果顯示具有核殼結(jié)構Fe@Fe2O3納米線能在90 min內(nèi)將溴酸鹽(BrO3-,1 mg/L)100%還原為溴離子(Br-),商品化Fe0對溴酸鹽的去除率為0%。中間產(chǎn)物測定顯示HBrO/BrO是一種重要的中間產(chǎn)物。通過鄰二氮菲捕獲亞鐵實驗發(fā)現(xiàn),亞鐵對于溴酸鹽的去除貢獻了34%。通過對比空氣、氬氣氣氛下溴酸鹽的去除效率,發(fā)現(xiàn)氬氣條件下溴酸鹽的去除速率是空氣條件下的2.56倍�；钚匝跷锓N的捕獲實驗結(jié)果表明：·02-、H2O2被捕獲后溴酸鹽的去除分別被抑制了82.4%、31.5%,而-OH被捕獲后,去除速率提高了1.19倍。結(jié)合XRD、SEM、XPS表征鐵納米線去除溴酸鹽前后的結(jié)構、形貌和組成成分分析,提出了核殼結(jié)構鐵納米線去除溴酸鹽的機理,并且去除過程的效率是高度依賴于表面亞鐵以及氧氣。2.阿特拉津是世界范圍使用的一種三嗪類除草劑,對動物以及人體的內(nèi)分泌產(chǎn)生極大的干擾。本文向零價鐵活化分子氧體系引入鎳離子改變阿特拉津常規(guī)的去除途徑,結(jié)果顯示Fe@Fe2O3/Ni(Ⅱ)/air降解阿特拉津的速率是Fe@Fe2O3/air體系的11.97倍。通過Fe@Fe2O3/Ni(Ⅱ)/air體系中間產(chǎn)物的分析可知阿特拉津降解首先是脫氯上氫,其次是脫烷基、側(cè)鏈氧化。阿特拉津脫烷基后的產(chǎn)物CAAT、AAT降解特性研究結(jié)果以及AAT降解產(chǎn)物的氫譜和中間產(chǎn)物拉曼光譜分析,證實阿特拉津在Fe@Fe2O3/Ni(Ⅱ)/air體系中三嗪環(huán)開環(huán)降解。
[Abstract]:The rapid development of the economy has improved people's lives, but also destroyed our living environment. The search for efficient and green means of environmental management has become the focus of attention of environmentalists. Iron is a kind of lively transition metal element. Iron, as a kind of environment-friendly material, has aroused the widespread concern of environmental protection workers in many environmental control ways. Zero valent iron has strong reductivity and can directly reduce and remove pollutants in the environment. At the same time, zero-valent iron can activate oxygen in air and remove organic pollutants by producing active oxygen species, even completely mineralized. In this paper, core-shell structure iron nanowire materials were synthesized. The efficiency and mechanism of removal of bromate and atrazine from water by nanometer zero-valent iron with this special structure were studied. The main contents of this paper are as follows: 1. Bromate is an advanced oxidation technology, especially ozone oxidation technology. Disinfection by-products from the process of toxic drinking water, It is defined by the International Cancer Organization as a potential carcinogen of class 2B. In this paper, the removal of bromate by core-shell Fe@Fe2O3 nanowires at neutral pH was discussed, and the effects of intermediate products in the reaction process and iron in the system were investigated. The effect of dissolved oxygen on the removal of bromate was also investigated. The results showed that the Fe@Fe2O3 nanowires with core-shell structure could reduce the bromate BrO3-1 mg / L ~ (100%) to Br-N in 90 min, and the removal rate of bromate by commercial Fe0 was 0%. The results show that HBrO/BrO is an important intermediate product. Iron contributes 34% to the removal of bromate. By comparing the removal efficiency of bromate in air and argon, It was found that the removal rate of bromate in argon was 2.56 times higher than that in air. The experimental results showed that the removal of bromate was inhibited by 82.4% and 31.5% respectively after the capture of H2O2 and -OH. The removal rate was increased by 1.19 times. The structure, morphology and composition of iron nanowires before and after removal of bromate were characterized by XRDX SEMX XPS, and the mechanism of removing bromate from core-shell structure iron nanowires was put forward. And the efficiency of the removal process is highly dependent on surface ferrous and oxygen. Atrazine is a triazine herbicide used worldwide. In this paper, nickel ion was introduced to the zero-valent iron activated molecular oxygen system to change the conventional removal pathway of atrazine. The results showed that Fe _ 2O _ 3 / Ni (鈪，

本文編號：1692597