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利用正交法得出次氯酸盐氧化法合成高铁酸钾的最佳工艺条件,以FTIR、XRD、SEM、EDS、TEM表征证实其纯度可达95%.在砷、铅单独及复合污染的处理中比较了K2 FeO4投加量、起始pH对处理效果的影响.实验表明,当砷、铅起始质量浓度为2 mg/L,溶液pH 6.5,铁砷质量浓度比为16或铁铅质量浓度比为4时,沉淀后水中砷、铅质量浓度均可低于10μg/L;K2 FeO4同样能有效处理砷铅复合污染,在K2 FeO4投加量为24 mg/L时,对砷、铅的去除率分别为99.30%和100%;与单独污染相比,低K2 FeO4投加量下,砷与铅的竞争关系明显.通过结合Visual MINTEQ化学平衡模拟软件对实验机理进行分析表明:高铁酸钾通过氧化、电中和及表面络合等作用去除水中砷、铅.“,”Potassium ferrate ( K2 FeO4 ) was synthesized by hypochlorite oxidation.Orthogonal method was applied to optimize the synthesis process.The obtained K2 FeO4 had a purity of 95% or higher.The synthesized K2 FeO4 was used as a coagulant to remove As( III) and Pb( II) in single and bi-solute systems.Effects of K2 FeO4 dosage and operating pH on the removal of As( III) and Pb( II) were studied.In the single system, results shows that at pH 6.5, Fe/As=16 ( wt/wt) and Fe/Pb=4 ( wt/wt) , the residual As and Pb were less than 10μg/L.In the bi-solute system, ferrate could remove As and Pb simultaneously.When ferrate dose was 24 mg/L, the removal rates of As and Pb were 99.30%and 100%, respectively.At low ferrate dose, the competitive adsorption behavior of As( III) and Pb( II) in the bi-solute system was observed.Visual MINTEQ software was used to calculate and sim-ulate metal speciation in solution at equilibrium aiming at elucidate the removal mechanism of As and Pb by potassi-um ferrate.