聚醚砜电催化有机膜的制备及其性能研究

发布时间：2019-05-27 05:24

【摘要】：电催化氧化技术可以将有机污染物分解为小分子有机物或者直接降解为水和二氧化碳。这可以使有机物降解的更高效、更彻底、更无害。因此,电催化技术在降解有机废水方面有着很广阔的应用前景。而在电催化过程中,电极是最关键的部分。相比于金属、难溶盐等电极,膜电极有比表面积大、适用范围广等特点,在有机废水处理方面得到了越来越多的关注。目前膜电极中的膜材料一般都是陶瓷膜等无机材料,这类膜电极最大的缺陷就是在反应过程中会出现催化物质脱落的情况,降低催化效果。本文将电催化技术与有机膜材料相结合,希望通过这种方法可以制备出一种具有优异性能的新的膜电极——聚醚砜电催化有机膜。相比于无机膜材料与催化物质结合不好的缺点,有机膜材料在与催化物质的结合上有着很好的优势。而且,有机膜材料选材广泛、制备方法简便、成本低廉。本实验以碳布为支撑体,通过在铸膜液中添加两种不同的电催化剂,用相转化法制备了两种含有不同催化剂的聚醚砜电催化有机膜。聚醚砜电催化有机膜是以聚醚砜为高分子聚合物,聚乙烯吡咯烷酮为添加剂,二甲基乙酰胺为溶剂制备铸膜液,通过在铸膜液中加入导电聚合物以及电催化剂,用相转化法制备出聚醚砜电催化有机膜。在电催化剂的选择方面,选择了 Sb-Sn02以及Pt/CNTs这两种不同的催化剂。将两种含有不同催化剂的聚醚砜电催化有机膜用SEM、EDX、XRD、XPS等表征方法进行表征分析,结果表明,含Sb-Sn02催化剂的聚醚砜电催化有机膜中含有聚苯胺和Sb-Sn02,含Pt/CNTs催化剂的聚醚砜电催化有机膜中含有聚苯胺和Pt/CNTs。聚醚砜电催化有机膜表面均匀、光滑、平整,截面出现指状孔。本实验选择直接红31染料为目标对象进行实验研究。研究了聚醚砜电催化有机膜的制备过程中导电聚合物、电催化剂含量对有机膜的电催化性能的影响,以及电压、染料的浓度、PH、电解质种类及浓度对染料降解效果的影响。实验结果表明,当染料的初始浓度为20mg·L-1、电压为2.6V、以NaCl为电解质、NaCl的质量分数为8%、中性条件下,对直接红31染料进行电催化降解,聚醚砜电催化有机膜对直接红31染料废水的降解效果比较好。实验表明,电催化和有机膜材料相结合制备出的膜电极——聚醚砜电催化有机膜,在降解直接红31染料的同时,膜表面以及膜孔内的有机污染物质也得到了降解,在一定程度上还起到了缓解聚醚砜电催化有机膜的膜污染的作用。
[Abstract]:Electrocatalytic oxidation can decompose organic pollutants into small molecules or degrade them directly into water and carbon dioxide. This can make organic matter degradation more efficient, more thorough, more harmless. Therefore, electrocatalytic technology has a broad application prospect in the degradation of organic wastewater. In the process of electrocatalysis, electrode is the most critical part. Compared with metal, insoluble salt and other electrodes, membrane electrode has the characteristics of large specific surface area and wide range of application, so it has attracted more and more attention in the treatment of organic wastewater. At present, the membrane materials in the membrane electrode are generally inorganic materials such as ceramic membrane. The biggest defect of this kind of membrane electrode is that the catalytic material will fall off in the reaction process, and the catalytic effect will be reduced. In this paper, the electrocatalytic technology is combined with organic membrane materials, and it is hoped that a new membrane electrode, polyethersulfone electrocatalytic organic membrane, can be prepared by this method. Compared with the poor combination of inorganic membrane material and catalytic material, organic membrane material has a good advantage in the combination of inorganic membrane material and catalytic material. Moreover, the organic membrane material is widely selected, the preparation method is simple and the cost is low. In this experiment, two kinds of polyethersulfone electrocatalytic organic membranes containing different catalysts were prepared by phase transformation method by adding two different electrocatalysts to the casting solution with carbon cloth as support. Polyethersulfone electrocatalytic organic membrane is prepared by using polyethersulfone as polymer, polyvinylpyrrolidone as additive and dimethyl acetamide as solvent. By adding conductive polymer and electrocatalyst to the casting solution, Polyethersulfone electrocatalytic organic membrane was prepared by phase transformation method. In the selection of electrocatalysts, two different catalysts, Sb-Sn02 and Pt/CNTs, were selected. Two kinds of polyethersulfone electrocatalytic organic membranes containing different catalysts were characterized by SEM,EDX,XRD,XPS and other characterization methods. The results showed that the polyethersulfone electrocatalytic organic membranes containing Sb-Sn02 catalysts contained Polyphenylamine and Sb-Sn02,. Polyethersulfone electrocatalytic organic membrane containing Pt/CNTs catalyst contains Polyphenylamine and Pt/CNTs. The surface of polyethersulfone electrocatalytic organic membrane is uniform, smooth and smooth, and finger pores appear in the cross section. In this experiment, direct red 31 dye was selected as the target object for experimental study. The effects of conductive polymer and electrocatalyst content on the electrocatalytic performance of polyethersulfone electrocatalytic organic membrane, as well as the effects of voltage, dye concentration, PH, electrolyte type and concentration on dye degradation were studied. The experimental results show that when the initial concentration of the dye is 20mg 路L ~ (- 1), the voltage is 2.6 V, the mass fraction of NaCl is 8% with NaCl as electrolyte, the direct red 31 dye is degraded by electrocatalysis under neutral conditions. Polyethersulfone electrocatalytic organic membrane has a good degradation effect on direct red 31 dye wastewater. The experimental results show that the membrane electrode, polyethersulfone electrocatalytic organic membrane, prepared by the combination of electrocatalysis and organic membrane material, not only degrades the direct red 31 dye, but also degrades the organic pollutants on the surface of the membrane and in the membrane pores. To a certain extent, it also plays an important role in alleviating the membrane fouling of polyethersulfone electrocatalytic organic membrane.
【学位授予单位】：扬州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X703

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