硅藻土负载纳米铁去除地下水硝酸盐氮污染

摘要

采用液相还原法制备纳米铁及硅藻土负载纳米铁, 并对材料进行扫描电镜 (SEM), X射线衍射 (XRD) 分析.负载纳米铁粒径80nm左右, 主要成分为Fe0.实验考察在不同硝酸盐氮初始质量浓度、纳米铁质量浓度、pH条件下, 硝酸盐氮的去除效果, 并进行动力学分析.结果表明, 纳米铁质量浓度越大, 去除效果越好.酸性条件更有利于脱硝反应的进行, 在硝酸盐氮质量浓度为40mg·L-1, pH为3, 负载纳米铁质量浓度为5g·L-1时, 硝酸盐氮的去除率可达99％.产物分析表明, 氨氮为反应的主要产物, 约占反应过程中去除硝酸盐氮的81％.反应符合一级动力学方程.%Nano-iron and Diatomite were prepared by liquid phase reduction, and scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to analyze the materials.The particle size of supported nano-iron was about 80 nm, and the main component was Fe0.The removal effect of nitrate nitrogen at the initial concentration of different nitrate nitrogen, the amount of nano-iron added and the pH condition was investigated, and the kinetic analysis was carried out.The results show that the greater the increase of nano-iron, the better the removal effect.The acidic condition is more favorable to the denitrification reaction, the removal rate of nitrate nitrogen can reach 99％ when the nitrate nitrogen mass concentration is 40 mg·L-1, pH 3 and the load of nano-iron is 5 g·L-1.The product analysis shows that ammonia nitrogen is the main product of the reaction, accounting for about 81％ of nitrate nitrogen removal during the reaction.The reaction conforms to the first-level kinetic equation.