响应曲面法优化硅藻土/TiO_2制备及深度处理氨氮废水

Optimization of TiO_2/Diatomite Preparation and Advanced Treatment of Ammonia-Nitrogen Wasterwater Using Response Surface Methodology

为深度降解废水中的氨氮,以纳米TiO_2和硅藻土为原料,利用化学沉淀法制备硅藻土负载TiO_2纳米材料.在单因素设计和试验基础上,采用Box-Behnken响应曲面法,以氨氮(NH3-N)去除率为响应值建立数学模型,分析影响催化剂降解氨氮废水的多种因素.模型优化结果显示:在焙烧温度500℃,焙烧时间3 h和负载量5 g条件下,制备得到的负载催化剂具有最佳的去除效果,氨氮去除率为73.11%.验证试验进一步验证了建立的响应曲面在负载催化剂制备工艺优化中的有效性.

Aim to deeply degrade ammonia nitrogen wastewater by TiO2/diatomite nanophotocatalyst which prepared from nanometer TiO2 and diatomite by the photochemical deposition method. The optimization of some parameters for the process of preparation the TiO2/diatomite and degradation rate of ammonia nitrogen in wasterwater by means of a Box-Behnken response surface methodology（ RSM） method,and the results were calcination temperature 500℃,calcination time 3 h and amount of diatomite on composite,and the photocatalytic degradation rate of ammonia nitrogen in wasterwater reached 73. 11%. The experimental data and model predications match well,which means that the RSM is very efficient in optimizing the preparation conditions of the TiO2/diatomite composite.