活性铁锰复合氧化物滤膜吸附除砷性能研究

Adsorption Characteristics of Arsenic(Ⅴ) by Active Fe-Mn Bimetal Oxide Filter

以化学挂膜方法制备出来的活性铁锰氧化物滤膜为研究对象,考察其表面特性及除砷性能。结果表明,应用准二级反应动力学方程(R^2=0.922)能够表征该活性铁锰复合氧化物对As(Ⅴ)的吸附过程;吸附等温线符合Langmuir方程(R^2=0.971),其饱和吸附容量为11.94 mg/g;活性铁锰氧化物滤膜的pH_(zpc)在2.5左右;天然地下水体中的碳酸根对该吸附剂的吸附除砷效果有较强的抑制作用,而其余共存阴、阳离子在中性水环境中对除砷的效果影响不大。在柱试验过程中,As(Ⅴ)浓度分别为200、280μg/L的地下水通过该滤柱处理后最终出水砷浓度均降为零,除砷效果较好。

The study was based on active Fe-Mn bimetal oxide filter prepared in the process of chemical catalytic oxidation filter in pilot scale, focusing on its surface characteristics and adsorption properties of arsenic （ V ）. The results showed that pseudo second-order kinetic model （ R^2 = 0. 922 ） could describe the arsenic adsorption process by active Fe-Mn bimetal oxide filter very well. Meanwhile, arsenic adsorption isotherm fitted well with the Langmuir equation （R^2 = 0. 971 ）, and the maximum ad- sorption capacity for arsenic was 11.94 mg/g. The pHzpc of active Fe-Mn bimetal oxide filter was around 2.5. The normally presented ions in natural underground water had no obvious side effect on arsenic ad- sorption by active Fe-Mn bimetal oxide filter except for carbonate. In column tests, groundwater containing arsenic 200 μg/L and 280 μg/L respectively was used as the feeding solution, and the arsenic concentration in the effluent reached zero, showing a good removal efficiency of arsenic.