零价铁去除水中锑(Sb)的研究

Removal of Antimony from Water by Zero-valent Iron

锑(Sb)是一种新兴的全球性污染物,在我国西南Sb矿区及周边地区Sb污染严重。本文研究了零价铁(ZVI)对Sb的去除效果,研究了ZVI投加量、Sb的初始浓度、pH值及阴离子等因素的影响。结果表明,ZVI对Sb具有较好的去除效果。通过ZVI对Sb去除动力学拟合,Sb的去除符合一级动力学方程;Sb的去除效率在偏酸性条件下比较高,在pH=5时,去除率达到68.98%;在pH=7时,Sb的去除率仅有23.36%;无机阴离子均在不同程度上影响Sb的去除,特别是PO43-对ZVI去除Sb有明显的抑制作用。

Batch experiments were conducted to investigate the effects of ZVI concentrations, the initial antimony concentrations, initial solution pH, and anions on antimony removal with zero-valent iron [ZVI]. It was demonstrated that antimony was removed rapidly from solution and the kinetics of antimony removal by ZVI follows the first-order equation. A linear relationship was observed, through batch testing, between the first-order rate constant （K） and the concentrations of ZVI. Under acidic condition, antimony removal by ZVI filings was faster. Greater than 68.98% of the antimony was removed at pH = 5, whereas, less than 68.98% of the antimony was removed at pH = 7. This study also investigated the efficiency of zero valent iron （ZVI） to remove antimony in the presence of low and high concentrations of various anions （phosphate, carbonate and sulphate）. Phosphate, particularly at higher concentrations, would significantly inhibit antimony removal.