纳米零价铁的制备及其对废水中铬的去除作用研究

摘要

Nano zero-valent iron was prepared by liquid phase reduction method,and the morphology of the prepared materials was analyzed by SEM.The nano zero-valent iron was used to treat the wastewater containing Cr.The effects of nano zero-valent iron dosage,initial concentration of Cr(Ⅵ) in wastewater,initial pH value of wastewater and reaction time on the removal rate of Cr(Ⅵ) were investigated.The optimum experimental conditions were as follows: the initial concentration of Cr(Ⅵ) in wastewater was 20 mg/L,the dosage of nano zero-valent iron was 500 mg/L,the initial pH value of wastewater was about 3,and the reaction time was 4.5 h.Under the optimum conditions,the removal rate of Cr(Ⅵ) can reach 99.45%.%采用液相还原法制备了纳米零价铁材料,借助扫描电镜对制备材料进行了微观形貌分析.利用制备的纳米零价铁对配制含铬废水的处理效果进行了考查,探究了纳米零价铁投加量、废水中Cr(Ⅵ)初始浓度、废水初始pH值及反应时间对Cr(Ⅵ)去除率的影响.实验结果表明使用该纳米零价铁处理含铬废水的最佳工艺条件为:废水中Cr(Ⅵ)初始浓度为20 mg/L、纳米零价铁投加量为500 mg/L、废水初始pH值为3、反应处理时间为4.5 h.在最佳工艺条件下Cr(Ⅵ)的去除率可达99.45%.