含磷铁尾矿对废水吸附除铬的实验研究

Experimental Study on Chromium Removal Performance of Wastewater by Phosphorus-Containing Iron Tailings

以废弃的含磷铁尾矿作为吸附剂对含铬(Cr^(6+))废水进行处理。采用XRD、SEM等表征技术,考察了初始pH值、吸附剂加入量、初始Cr^(6+)浓度、吸附时间和吸附温度等因素对除Cr^(6+)效果的影响。含磷铁尾矿对Cr^(6+)的吸附是物理吸附、静电吸附和化学吸附等综合作用的结果。实验结果表明,在初始pH值为5.0~7.5,初始Cr^(6+)质量浓度为40~50 mg L,吸附剂加入量为20 g L,吸附剂粒度小于0.15 mm,吸附时间为25 min,吸附温度为25℃的最佳实验条件下,含磷铁尾矿对Cr^(6+)的吸附率达99%以上,且吸附后的Cr^(6+)质量浓度低于0.5 mg L。

Waste phosphorus-containing iron tailings are used as adsorbents to treat chromium-containing wastewater.The effects of initial pH,adsorbent addition,initial Cr^(6+)concentration,adsorption time and adsorption temperature on Cr^(6+)removal are investigated using XRD,SEM and other characterization techniques.The Cr^(6+)adsorption mechanism of phosphorus-containing iron tailings is the result of the combined function of physical adsorption,electrostatic adsorption and chemical adsorption.The experimental results show that the adsorption rate of Cr^(6+)is above 99%under the optimal experimental conditions that initial pH is 5.0-7.5,initial Cr^(6+)concentration is 40-50 mg L,adsorbent addition is 20 g L,adsorbent particle size is less than 0.25 mm,adsorption time is 25 min and adsorption temperature is 25℃,and the adsorption concentration of Cr^(6+)is lower than 0.5 mg L.