硅藻土负载纳米铁去除地下水硝酸盐氮污染

Removal of Nitrate and Nitrogen Pollution from Groundwater by Nano-Iron Supported on Diatomite

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 Fe 0.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.