纳米零价铁材料选择性去除含砷、锑废水的研究
Study on Selective Removal of Arsenic and Antimony Containing Wastewater by Nano Zero-Valent iron Materials

本研究以砷(As)和锑(Sb)为目标污染物，采用液相还原法制备了纳米零价铁(nZVI)材料，探讨了不同反应条件对nZVI选择性吸附砷锑的影响。实验结果表明，在机械搅拌条件下，当nZVI投加量为2.0 g/L、砷锑浓度为10 mg/L、pH为3时，溶液中砷和锑的去除率均可达到99.99%。通过XRD分析，发现nZVI在反应过程中发生了氧化，并与砷、锑形成共沉淀；此外，As和Sb之间也会反应生成沉淀，导致溶液中砷和锑浓度下降。XPS分析表明，nZVI的去除机制主要依赖于吸附和还原反应的共同作用。此外，nZVI表面的FeOOH能够将As (III)氧化为As (V)，并吸附As (III)和As (V)，从而有效去除水溶液中的砷，而对Sb的去除主要是通过吸附。综上所述，nZVI材料在去除含砷锑溶液中的砷和锑方面表现出较好的效果，且其去除机制主要为吸附与还原反应的协同作用，具有良好的应用前景。
In this study, nano zero-valent iron (nZVI) materials were prepared by liquid phase reduction method with arsenic (As) and antimony (Sb) as the target pollutants, and the effects of different reaction conditions on the selective adsorption of arsenic and antimony by nZVI were investigated. The experimental results showed that the removal rate of both arsenic and antimony in the solution could reach 99.99% under the mechanical stirring condition when the dosage of nZVI was 2.0 g/L, the concentration of arsenic and antimony was 10 mg/L, and the pH was 3. The results showed that the nZVI could remove 99.99% of arsenic and antimony from the solution under the mechanical stirring condition. Through XRD analysis, it was found that nZVI was oxidized during the reaction process and formed co-precipitation with arsenic and antimony; in addition, the reaction between As and Sb also produced precipitation, resulting in a decrease in the concentration of arsenic and antimony in the solution. XPS analysis showed that the removal mechanism of nZVI mainly depended on the combined effect of adsorption and reduction reactions. In addition, FeOOH on the surface of nZVI can oxidize As (III) to As (V) and adsorb As (III) and As (V), which effectively removes arsenic from aqueous solution, while the removal of Sb is mainly by adsorption. In summary, nZVI material shows better effect in removing arsenic and antimony in arsenic-containing antimony solution, and its removal mechanism is mainly the synergistic effect of adsorption and reduction reaction, which has good application prospects.