光电催化去除柠檬酸铵中的氨氮

采用阳极氧化法制备了二氧化钛纳米管电极，以制备的二氧化钛纳米管电极为光阳极，采用钛片作为阴极，通过光电催化氧化方法对柠檬酸铵中氨氮进行了去除研究。考察了外加偏压、初始pH值、初始柠檬酸铵浓度，电解质的浓度对氨氮去除的影响。结果表明：与传统的光催化法和电化学法相比，光/电法在柠檬酸铵中氨氮降解过程中存在良好的协同效应；在电压为1.0 V，pH为12，NaCl浓度为0.1 mol·L-1，初始投加柠檬酸铵的量以N计为25 mg·L-1的条件下，紫外光照射下，采用二氧化钛纳米管电极，反应120 min后，柠檬酸铵中氨氮的降解达到60%左右。其中，柠檬酸铵中氨氮的降解产物中N2占82.6%。CaCl2对降解柠檬酸铵起到了加速活化作用。

Photoelectrocatalytic removal of ammonia nitrogen inammonium citrate using titania dioxide nanotube electrode

A titanium-dioxide nanotube-array electrode was prepared by the anodic oxidation process using the cyclic voltammetry method. Next, this electrode was used as a photo-anode and a titanium sheet was used as a cathode to removal ammonia nitrogen from ammonium citrate. The influences of various parameters (i.e., the voltage bias, the initial solution pH, initial concentration of ammonium citrate, and the concentration of electrolyte solution) on the degradation effect were also investigated. The results indicated that the photo-electrical method achieved an excellent synergistic effect compared to the traditional photocatalytic and electrochemical methods. For example, at 1.0 V and an initial solution pH of about 12, the concentrations of NaCl and ammonium were adjusted to 0.1 mol·L-1and 25 mg·L-1. The removal rate of ammonia nitrogen reached as high as 60% in 120 min and 82.6% degradation of total ammonia nitrogen to N2 was observed. The addition of CaCl2 can accelerate the process.