纳米Ce/SnO_2在水产养殖废水处理中光催化性能研究

Photocatalytic efficiency of nano-Ce / SnO_2 in the treatment of aquaculture wastewater

采用化学共沉淀法制备了稀土Ce/SnO_2光催化剂,以XRD、SEM等测试手段对其进行晶型、粒径、形貌等的表征。催化剂为四方晶系金红石结构,平均粒径在40～50 nm之间。在可见光条件下,用制备的光催化剂降解模拟水产养殖废水中的NH4-N,实验结果表明,对NH_4-N去除效果的影响顺序为：Ce的掺杂比〉煅烧温度〉NH_4-N初始浓度〉催化反应时间〉催化剂投加量。根据正交以及验证实验,光催化降解最优反应条件为：Ce/SnO_2投加量为0.8 g/L,Ce掺杂量为1.0%,煅烧温度为500℃,NH_4-N初始浓度为50mg/L,催化反应时间为2 h。NH_4-N去除率可以达到92.7%。

Nano-Ce / SnO_2 photocatalyst was obtained by the chemical precipitation method,The particle crystal form,size of powders,morphology have been characterized using the X-ray diffraction and electron microscope. It was found that the prepared catalysts were quartet rutile structure and the average particle size were between 40 to 50 nm. Under visible light,the photocatalytic oxidation of ammonia nitrogen in seawater was researched by using prepared nano-SnO_2. The influence orders of degradation as follows： Ce-doping ratio calcination temperature initial concentration of ammonia-N reaction time photocatalyst dosage. According to the orthogonal experiment and the verified experiment,The optimum reaction conditions： photocatalyst dosage is 0. 8 g / L,Ce-dopping ratioa is 1. 0%,calcination temperature is 500℃,initial concentration of ammonia-N is 50 mg / L,reaction time is 2 h. Under such condition,the removal rate of ammonia-N can reach 92. 7%.