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题名	臭氧在不同催化剂表面的转换及水中医药品污染物的去除机制
作者	邴吉帅
学位类别	博士
答辩日期	2016-05
授予单位	中国科学院研究生院
授予地点	北京
导师	胡春
关键词	催化臭氧氧化，活性氧物种，药物，Lewis 酸性位，多价态金属 Catalytic ozonation, Reactive oxygen species，Pharmaceutical, Lewis acid site, Multivalent metal
其他题名	Conversion of ozone on different catalyst surfaces and the mechanism of pharmaceuticals removal in water
学位专业	环境工程
中文摘要	多相催化臭氧氧化技术具有对有机污染物氧化彻底、稳定性好、催化剂可再生重复使用等优点，近年来成为环境领域的研究热点。但是目前对于水相反应，多相催化臭氧氧化反应的机理研究仅仅局限于理论上的推测，缺乏系统而深入的研究。本论文首先研究了臭氧在不同氧化物表面的转化和污染物的降解，揭示催化臭氧氧化机理；并基于臭氧在催化剂表面的转化规律，设计催化剂，控制催化臭氧氧化水中医药品污染物的转化与有毒副产物溴酸盐的生成。最后，将催化剂固定化，通过固定床循环实验考察其应用于实际含溴原水处理工艺的可行性。主要研究内容和结果如下：     1. 确定臭氧在不同氧化物表面的转化规律，发现MCM-41 和α-Fe2O3 没有酸性位，臭氧物理吸附于催化剂表面孤立的羟基基团和氢键羟基基团不分解，主要是由于这两种羟基基团阻止了臭氧和MCM-41 和α-Fe2O3 氧化物中心原子的直接接触。因此在这两种氧化物的臭氧悬浆中臭氧分子是主要的活性氧物种。而在γ-Al2O3、α-FeOOH、Fe3O4、α-MnO2 和β-MnO2 的臭氧悬浆中，臭氧能够和水分子竞争并取代这些氧化物表面Lewis酸性位上的氢键羟基基团和桥联的羟基基团发生有效分解；对于γ-Al2O3，臭氧在其表面分解产生活性原子氧（ 3+  Al -*O），活性原子氧是主要的活性氧物种；而对于多价态的金属氧化物α-FeOOH、Fe3O4、α-MnO2 和β-MnO2，多价态金属的电子循环有利于臭氧分解产生OH 和O2-自由基，并且有机物的加入能促进多价态金属的电子循环，从而产生更多的OH 和O2-自由基。     2. 基于臭氧在不同氧化物表面的转化规律，成功设计并制备了Lewis 酸性位强化的臭氧化催化剂Fe2O3/Al2O3@SBA-15。将其用于处理布洛芬，发现该催化剂有较高的催化活性和稳定性。表征结果表明Al3+取代SBA-15 表面≡Si-OH 基团上的氢原子形成Al-O-Si 键，这不仅导致Al2O3 和Fe2O3 在SBA-15 表面的高度分散，而且极大的增加了SBA-15 表面的Lewis 酸性位。原位衰减全反射红外光谱，拉曼光谱和电子顺磁共振光谱证实臭氧吸附于Al3+的Lewis 酸性位上分解产生活性原子氧，在Fe3+的Lewis 酸性位上分解产生吸附的羟基自由基（OHads）和超氧自由基（O2-），而Fe2O3/Al2O3@SBA-15催化剂中Al3+和Fe3+的Lewis 酸性位共同作用促进臭氧分解产生更多的OH 和O2-自由基，从而对布洛芬有最高的矿化率。     3. 基于臭氧在不同氧化物表面的转化规律，成功设计并制备了酸性可调的介孔固体酸γ-Ti-Al2O3 催化剂。γ-Ti-Al2O3 对布洛芬、苯妥英、苯海拉明、阿昔洛韦、磺胺甲恶唑和双氯酚酸钠6 种常用药物表现出极高的催化活性和稳定性。表征结果表明Ti4+掺杂进入γ-Al2O3 骨架形成Al-O-Ti 键，钛以正四面体结构存在，这极大的增强了γ-Al2O3的Lewis 酸性位，特别是中等强度的Lewis 酸性位。拉曼光谱和电子顺磁共振光谱表明臭氧在 γ-Ti-Al2O3 表面分解产生活性原子氧（ Al3+ -*O）和过氧物种（ 4+2  Ti -*O ），而不是羟基自由基和超氧自由基。这种吸附于催化剂表面的原子氧和过氧物种可以直接和吸附于催化剂表面的有机酸反应使其矿化，从而对药物有很高的矿化率。这种催化剂有更好的水质适应性，从而有更广阔的应用前景。     4. 基于γ-Ti-Al2O3 高的催化活性和催化臭氧氧化过程中铁的氧化还原反应，成功设计并制备了γ-Fe-Ti-Al2O3 催化剂用于催化臭氧氧化水中有机物及溴酸盐生成控制研究。在含布洛芬和溴离子的配水中，γ-Fe-Ti-Al2O3 催化臭氧氧化含溴废水过程能够有效阻断溴酸盐的生成，并在含溴酸盐和布洛芬的配水中实现溴酸盐的还原。研究证实了γ-Fe-Ti-Al2O3 中Fe2+/Fe3+电子循环实现了溴酸盐的阻断还原，并且腐殖酸的加入能够强化催化剂对溴酸盐的阻断还原。进一步将催化剂固定化在上海杨树浦水厂进行中试研究，通过固定床循环实验考察其应用于实际含溴原水处理工艺的可行性。设备运行270h，TOC 的去除率约为50%，没有溴酸盐的生成，说明铁铝复合小球是一种有前景的臭氧化催化剂。
英文摘要	Heterogeneous catalytic ozonation has been received increasing attention in recent years because of its potentially higher effectiveness in the degradation and mineralization of refractory organic pollutants, good stability and repeated use of renewable catalyst. But now for the reaction in the water phase, the reaction mechanism is mainly based on speculation, lack of systematic and in-depth study. This thesis firstly studies conversion of ozone on the surface of different oxides and the degradation of pollutants, revealing the mechanism of catalytic ozonation. Based on the law of ozone transformation on oxides surface, catalysts were designed and used to control the transformation of pharmaceuticals and the generation of toxic by-product bromate. Finally, the catalyst was immobilized, and the feasibility of its application in the treatment of raw water containing bromide was investigated by the fixed bed cycle test. The main research contents and results are as follows:     1. The transformation law of ozone on different oxide surface was confirmed. It is found that the MCM-41 and Fe2O3 have no acidic sites, ozone was physical adsorption on isolated hydroxyl groups and hydrogen-bond hydroxyl groups of MCM-41 and α-Fe2O3 does not decompose, which was mainly due to these two kinds of hydroxyl groups prevent the direct contact of ozone with the center atoms of oxides. Therefore, ozone molecules are the main reactive oxygen species in these two oxide suspensions with ozone. While in γ-Al2O3, α-FeOOH, Fe3O4, α-MnO2 and β-MnO2 suspensions with ozone. Ozone could compete with water moleculars, replace the hydrogen-bond hydroxyl groups and bridging hydroxyl groups on these oxides and effective decompose. Ozone was mainly decomposed into surface atomic oxygen species when it was adsorbed on valence immutable Lewis acid sites of γ-Al2O3, moreover, generated more OH and O2- radicals on the surface of multi-valence oxides (α-FeOOH, Fe3O4, α-MnO2 and β-MnO2) due to their redox roles, and the complexes of pollutants and byproducts with multi-valence metal are conducive to its mineralization by generating more OH and O2- radicals.     2. Based on the law of the conversion of ozone on the surface of different oxides, the Lewis acid enhanced ozonation catalyst Fe2O3/Al2O3@SBA-15 was successfully designed and prepared. Fe2O3/Al2O3@SBA-15 was found to be highly effective for the mineralization of ibuprofen aqueous solution with ozone. The characterization studies showed that Al-O-Si were formed by the substitution of Al3+ for the hydrogen of surface Si-OH groups, not only resulting in high dispersion of Al2O3 and Fe2O3 on SBA-15, but also inducing the greatest amount of surface Lewis acid sites. By the studies of in situ ATR-FTIR, in situ Raman and EPR spectra, the chemisorbed ozone was decomposed into surface atomic oxygen species at the Lewis acid sites of Al3+ while it was converted into surface adsorbed OHads and O2- radicals at the Lewis acid sites of Fe3+. The combination of both Lewis acid sites of iron and aluminium onto Fe2O3/Al2O3@SBA-15 enhanced the formation of OHads and O2 - radicals, leading highest reactivity.     3. Based on the law of the conversion of ozone on the surface of different oxides, an mesoporous solid-acid γ-Ti-Al2O3 catalyst was successfully designed and prepared. γ-Ti-Al2O3 revealed excellent catalytic ozonation activity and stability for mineralization of six drugs in aqueous solution, including ibuprofen, sulfamethoxazole, phenytoin, diphenhydramine, diclofenac sodium and acyclovir. The characterization studies showed that titanium was incorporated into the framework of γ-Al2O3 by Al-O-Ti linkage, locating at tetrahedrally coordinated sites, which increased the Lewis acid sites of γ-Al2O3, especially the medium acid sites. The surface atomic oxygen (  Al3+ -*O ) and peroxide species ( 4+ 2  Ti -*O ) were commonly generated rather than hydroxyl radical from catalytic decomposition of ozone in γ-Ti-Al2O3 suspension on the basis of EPR and in situ Raman measurements. Furthermore, it was verified that the high mineralization of the tested pharmaceuticals came from the surface oxidization of organic acid intermediates by the common role of the surface atomic oxygen and peroxide species. Thus the catalyst has  better water quality adaptability, thus has broader application prospects.     4. Based on the high catalytic activity of γ-Ti-Al2O3 and oxidation reduction reaction of iron in catalytic ozonation process, γ-Fe-Ti-Al2O3 was successfully designed and prepared for ozonation of organics and control the generation of bromate in water. In the water containing ibuprofen and Br , γ-Fe-Ti-Al2O3 catalytic ozonation process could effectively block the formation of bromate. In the water containing bromate and ibuprofen, γ-Fe-Ti-Al2O3 could reduce bromate. The study confirmed that the electronic recycling of Fe2+/Fe3+ contribute to the reduction and blocking of bromate, and the addition of humic acid can strengthen the process. Furthermore, this kind of catalyst was fixed to Fe/Al oxide pellets and was used for the treatment of Br containing water obtained from Shanghai Yangshupu water plant. Equipment operation 270 h, TOC removal rate was about 50% and without the formation of bromate. The results showed that Fe/Al oxide pellets is a promising ozonation catalyst.
内容类型	学位论文
源URL	[http://ir.rcees.ac.cn/handle/311016/36776]
专题	生态环境研究中心_环境水质学国家重点实验室
推荐引用方式 GB/T 7714	邴吉帅. 臭氧在不同催化剂表面的转换及水中医药品污染物的去除机制[D]. 北京. 中国科学院研究生院. 2016.

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