光电去除水体中含氮化合物以及阴极重金属回收的研究

发布时间：2018-09-06 16:39

【摘要】：由于工农业生产的日趋发展导致含氮化合物的排放量过度增加。含氮化合物已成为环境的主要污染物,并受到了社会各界的广泛关注。开发经济、高效的除氮技术已成为水污染治理的重点和热点。其中,重金属又存在易与含氮络合物相结合的特点,常规的水处理方法对这一复杂水质难以有效去除,因此需要寻找一种既能有效去除氨氮又能回收重金属的方法。利用阳极氧化法制备的稳定性能良好的二氧化钛纳米管电极作为光阳极,钛片作为阴极对水体中氨氮的不同形式(无机氨氮形式、有机氨氮形式、含氮重金属络合物形式)进行光电催化降解和回收重金属的实验。对光电降解水体中的氨氮考察了外加偏压、初始p H值、初始氨氮的浓度、电解质的浓度以及类型、络合物配比等条件实验。对光电协同效应的主要机理进行了探讨。对无机氨氮形式、有机氨氮形式的光电降解过程中的产物进行了分析,结果表明光电协同法去除水体中氨氮的主要产物为氮气,因此可以认为光电法催化氨氮可为实现工业化提供一定的理论依据。最后分析了光电催化降解含氮重金属络合物的降解路径,结果表明主要通过羟基自由基实现其破络合。借助XPS表征手段分析了阴极的还原过程。
[Abstract]:Due to the development of industrial and agricultural production, the emissions of nitrogen compounds increase excessively. Nitrogen compounds have become the main environmental pollutants, and have been widely concerned by all walks of life. Development of economic and efficient nitrogen removal technology has become the focus and focus of water pollution control. Among them, heavy metals are easy to be combined with nitrogen-containing complex compounds. It is difficult to remove the complex water by conventional water treatment methods. Therefore, it is necessary to find a method that can effectively remove ammonia nitrogen and recover heavy metals. Titanium dioxide nanotube electrode with good stability prepared by anodic oxidation method was used as photoanode and titanium sheet as cathode for different forms of ammonia nitrogen in water (inorganic ammonia nitrogen, organic ammonia nitrogen). The photocatalytic degradation and recovery of heavy metals were carried out in the form of nitrogen-containing heavy metal complexes. The conditions of photodegradation of ammonia nitrogen in water were investigated, such as applied bias voltage, initial pH value, initial concentration of ammonia nitrogen, concentration and type of electrolyte, and ratio of complex. The main mechanism of photoelectric synergistic effect is discussed. The products in the photodegradation process of inorganic ammonia nitrogen and organic ammonia nitrogen were analyzed. The results showed that the main product of removing ammonia nitrogen in water by photoelectric synergistic method was nitrogen. Therefore, it can be concluded that photocatalysis of ammonia nitrogen can provide a theoretical basis for industrialization. Finally, the degradation path of photocatalytic degradation of nitrogen-containing heavy metal complex was analyzed. The results showed that the degradation pathway was mainly achieved by hydroxyl radical. The reduction process of the cathode was analyzed by means of XPS characterization.
【学位授予单位】：华北理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X52

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