修饰石墨基二氧化铅电极电催化氧化降解苯胺

Electro-catalytic Oxidative Degradation of Aniline by Modified Graphite-based Lead Dioxide Electrode

选择石墨作为基体,采用电沉积的方法制备出掺杂镧元素修饰的二氧化铅电极.通过对该电极进行XRD和SEM测试,发现电极的表面主要成分为β-PbO2,底层为α-PbO2;镧金属的氧化物嵌入到PbO2晶格当中,使晶形发生显著改变;电极表面致密均匀,空隙率大,利于对目标有机物吸附和发生电催化氧化反应.以该修饰电极为阳极,石墨电极为阴极,对苯胺模拟废水进行电催化氧化处理,分别考察了阴离子种类、电流密度、进水质量浓度、反应初始pH值对苯胺和COD去除率的单因素影响.该修饰二氧化铅电极对苯胺的电化学氧化降解反应基本符合一级反应动力学规律.

The La-doped lead dioxide electrode was prepared through electrodeposition by using graphite as base in the experiment. The major component of the electrode surface was β-PbO2, and the bottom was α-PbO2 by XRD and SEM. Lanthanum oxide embedded into the crystal lattice of PbO2 so as to remarkably change the crystal shape. The compact and lacunose electrode surface was beneficial to adsorption of target organics and electro-catalytic oxidation reaction. The simulated aniline wastewater was treated by electrochemical oxidation with Ladoped lead dioxide anode and graphite cathode. The influences of different single factors including anion, chloride ion concentration, current density, influent concentration and initial pH on aniline and COD removal rate were also studied. The dynamics analysis of the process of electrolysis indicates that the aniline removal basically accords with the first order kinetics.