亲水性陶瓷复合膜的制备及其分离性能研究

发布时间：2018-02-21 12:55

  本文关键词： 陶瓷膜 含油废水 膜技术 聚偏氟乙烯 有机-无机复合膜　出处：《华南理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着科技的不断进步和人类生活水平质量的逐步提升,由工业生产制造以及人类生活造成的水污染现象也是日趋严重,其中含油废水就是淡水资源的一个重要污染源。膜分离技术有着能耗低、污水处理效率高、占地面积小的特点,被当作解决当前水污染问题的优选技术。但是,无论是何种类型的分离膜都要面临着膜污染问题。本课题是将有机材料和无机材料联合起来制备出有机-无机复合膜,在保持化学稳定性好、热稳定性高的基础上,还能改善复合膜的亲水性,增强复合膜的机械强度,进而从根本上减小膜污染造成的影响,延长膜的使用时间。本文以聚偏氟乙烯(PVDF)和聚乙二醇(PEG)来配制铸膜液,以经过二氧化硅溶胶和硅烷偶联剂处理过的无机陶瓷膜管为载体,采用干燥固化方法成膜。通过红外吸收光谱、热重分析、扫描电子显微镜、表面接触角测试仪对复合膜进行表征。探究了涂膜方法、PVDF、PEG浓度以及热处理温度对复合膜性能的影响。结果显示:复合膜表面成功引入羟基基团,并且复合膜的热稳定性也较高,在509℃左右才完全分解;采用滚涂的方式,涂覆浓度为6wt.%PVDF-6wt.%PEG铸膜液,在50℃条件下制备的陶瓷复合膜性能最优,纯水通量在0.1MPa下达到2119.6 L/(m2·h)。在含油废水的处理过程中,研究了膜的制备过程、进料液中油浓度,操作压力,过滤时间对复合膜油水分离性能的影响。结果表明采用滚涂的方式,涂覆浓度为6wt.%PVDF-9wt.%PEG铸膜液,在50℃条件下制备的复合膜油水分离性能最佳,在0.2MPa压力下,过滤200mg/L的含油废水,经过300min后膜通量维持在32 L/(m2·h),通过紫外分光光度法检测到滤出液中油浓度为4.2mg/L,截油率高达97.8%,达到直接排放标准。将复合膜用于大肠杆菌水溶液的净化处理时,复合膜的除菌率高达99.9998%,在SEM下观察到膜表面形貌,计算膜的孔径大约为25nm。
[Abstract]:With the continuous progress of science and technology and the gradual improvement of the quality of human life, the phenomenon of water pollution caused by industrial production and human life is becoming more and more serious. The membrane separation technology has the characteristics of low energy consumption, high efficiency of sewage treatment and small area. It is regarded as the optimal selection technology to solve the current water pollution problem. No matter what kind of separation membrane is faced with membrane fouling problem, this subject is to combine organic and inorganic materials to prepare organic-inorganic composite membrane, on the basis of maintaining good chemical stability and high thermal stability. It can also improve the hydrophilicity of the composite membrane, enhance the mechanical strength of the composite membrane, reduce the influence caused by membrane fouling, and prolong the service time of the membrane. In this paper, PVDF and PEG were used to prepare the casting solution. The inorganic ceramic membrane tube treated by silica sol and silane coupling agent was used as the carrier. The film was formed by drying and curing method. The film was obtained by infrared absorption spectrum, thermogravimetric analysis and scanning electron microscope. The surface contact angle tester was used to characterize the composite film. The effects of PEG concentration and heat treatment temperature on the properties of the composite film were investigated. The results showed that the hydroxyl group was successfully introduced on the surface of the composite film, and the thermal stability of the composite film was also high. The ceramic composite membrane prepared at 50 鈩，

本文编号：1522030