【作者】 郑国华；

【导师】 柳丽芬；

【作者基本信息】 大连理工大学 ， 环境工程， 2008， 硕士

【摘要】 为保护环境和人体健康，去除和净化水中的微污染物，多采用反渗透、纳滤、高级催化氧化和吸附的方法，但存在的问题是吸附造成的膜污染、氧化副产物毒副作用和分离去除不彻底的问题。本研究采用溶胶凝胶法制备出含TiO₂、碳纳米管或活性炭纤维、具有吸附分离和催化净化特点的复合膜，用于去除水中的低浓度有机污染物。使用这种先吸附和分离、后进行氧化反应来净化吸附的污染物的复合膜，既可避免副产物对膜分离净化出水的污染，又可解决膜上吸附的有机污染物的净化问题。通过电子扫描电镜（SEM）、X射线衍射（XRD）、紫外-可见吸收光谱（UV-Vis）、傅立叶变换红外光谱（FT-IR）等手段对所制的复合膜及膜上纳米TiO₂进行表征分析。采用溶胶凝胶和浸渍涂敷方法，基膜上负载由钛酸四丁酯水解制备的含铈离子纳米Ti02和不同比例碳纳米管（MWNTs）的催化吸附复合膜（110℃下干燥），进行了静态吸附含双酚A的微污染模拟水样至吸附平衡实验。所制备的MWNTs／TiO₂／聚酯复合膜对50mL 10mg／L的双酚A具有较高的吸附去除效果。当MWNT／TiO₂中MWNTs=46．00（wt．％）时，对BPA的吸附效果最好，可达71．5％。吸附达平衡的复合膜，直接进行UV光催化或者UV-Fenton反应，可有效氧化降解吸附的污染物。UV-Fenton 1h后MWNTs／TiO₂／聚酯复合膜的吸附去除率，与第一次吸附时的吸附去除率相比，恢复率达到57％，接近单独UV 2h后恢复率（33％）的两倍。采用溶胶凝胶和浸渍涂敷方法，基膜上负载由钛酸四丁酯水解制备含铈离子纳米TiO₂和不同比例活性炭纤维（ACF）的催化吸附复合膜（110℃下干燥），分别考察了静态吸附含双酚A的微污染模拟水样实验和动态吸附．过滤含双酚A和高岭土的悬浊模拟水样实验。所制备的ACF／TiO₂／聚酯复合膜对50mL 10mg／L的双酚A具有较高的吸附去除效果。当ACF／TiO₂中ACF=11．33（wt．％）时，对双酚A的吸附去除率可达93％；当ACF=29．87（wt．％）时复合膜对双酚A溶液吸附0．5h后去除率接近100％；动态吸附-过滤实验结果表明，该复合膜在对双酚A有60％的吸附去除率的同时，对模拟水样中固体悬浊物质具有较高截留特性，浊度去除率达98．7％。UV-Fenton 2h后ACF／TiO₂／聚酯复合膜吸附功能恢复较好，与第一次吸附时的吸附去除率相比，恢复率达到72％。动力学分析表明活性碳纤维对双酚A的吸附符合准一级动力学方程。在钛酸四丁酯（TBOT）溶胶中引入硅酸四乙酯（TEOS）可提高复合膜在UV-Fenton处理后的稳定性。而且SiO₂／TiO₂／ACF／聚酯复合膜的吸附恢复率最高达到了90％。更多还原

【Abstract】 In order to protect the environment and human health, RO, NF or AOPs were used to remove micropollution to improve water quality. However, membrane fouling, oxidation by-products and their toxic side effect influence their application to some degree. The purpose of this paper is to develop a new cost-effective method to remove and mineralize trace organic pollutants containing multi-walled carbon nanotubes （MWNTs） and activated carbon fiber（ACF） and nano-sized TiO₂ particles, a combination of adsorbent and photo-catalyst functional membrane by using a sol-gel and dip coating method on Polyester （PET） membrane. Adsorption and then oxidation the micropollution on the seprated membrane. As the pollutants were mineralized, the oganic pollution of membrane effluent can be put an end.The prepared composite membranes and nano-TiO₂ particles were characterized by SEM, XRD,UV-Vis, FT-IR, et al.MWNTs were added to the sol gel solution derived from hydrolysis of Ti（OC₄H₉）₄ and doped with Ce³⁺, which was used to dip-coating polyester filter membrane, thus formed composite membrane was used to adsorb micropollutant from water statically. After adsorption reaching an equilibrium,the membrane were removed, to membrane saturated with pollutant bisphenol A, either photocatalysis or UV/Fenton reaction was applied to oxidize and degrade the adsorbed pollutant, to avoid by-product pollution of the purified water. The best adsorptive removal of BPA by MWNTs/TiO₂ composite membrane（MWNTs =46.00（wt.%）） was 71.5%, also measured was the repeated use of the membrane in pollutant adsorption removal and adsorption capacity regeneration using advanced oxidation（photo-catalysis）. Compared with the initial adsorption removal rate, the adsorption restoration rate nearly doubled using 1h UV/Fenton oxidation than 2h UV alone 33% to 57%.Also, a series of composite functional membrane containing ACF powder （<240 mesh） and Ce³⁺-TiO₂, a combination of adsorbent and photo-catalyst on PET filter cloth, was prepared by using a sol-gel and dip coating method（drying at the temprature of 105℃）. Both the static adsorption experiment and dynamic adsorption experiment were carried out. The results showed the following: The BPA adsorption removal rate by composite membrane with 11.33 and 29.87wt.% ACF in ACF/TiO₂ was 93% and 100%; The dynamic adsorption experiment showed that as high as 60% BPA removal was achieved in dynamic filtration /adsorption test, which removed 98.7% Koalinite solid suspends at the same time. Also measured was the repeated use in BPA removal and adsorption capacity regeneration using advanced oxidation（photo-catalysis）. Compared with the initial adsorption removal rate, the adsorption restoration rate were 72% after 2h UV and Fenton reagents’ oxidation for the second time adsorption. The adsorption process followed a first order kinetics. Introducing TEOS in the preparation of sol gel solution and subsequent coating to form composite membrane, improved membrane adsorption stability after regeneration treatment by UV-Fenton. 90% highest adsorption retoration was reached for SiO₂/TiO₂/ACF membrane.更多还原