粘土负载纳米零价铁去除水中的 Cr（Ⅵ）

摘要

Nanoscale zero-valent iron(nZVI) was prepared by reducing ferric ion (FeCl3· 6H2O) to Fe0 using the borohydride ( NaBH4 ) reduction method ,nZVI was loasded onto clay as a supported material ( C-nZVI) .By studying the removal of environmental pollutant Cr (Ⅵ) from water by C-nZVI under these conditions (initial pH,initial concentration of reagent,the dose of nZVI).The result showed that Cr(Ⅵ) removal increased with the decreasing of initial pH ,initial concentration of Cr (Ⅵ) and the increasing of C-nZVI amount at room temperature ,about 95%of Cr(Ⅵ) was removed from aqueous solution using C-nZVI at an initial condition of 10 mg/L Cr(Ⅵ) within 60 min under the conditions of 30 g/L of C-nZVI, pH 4.14.The mechanism of Cr(Ⅵ) removal using C-nZVI was speculated which mainly involved to the reduction reaction and co-precipitation .%采用NaBH4还原FeCl3制备纳米铁（nZVI），利用标准粘土为载体制备了负载纳米铁（C-nZVI），用于去除水体中的重金属Cr（Ⅵ），考察起始pH、Cr（Ⅵ）初始浓度、C-nZVI的量对Cr（Ⅵ）去除率的影响。结果表明，Cr（Ⅵ）的去除随着起始pH和Cr（Ⅵ）初始浓度的降低及纳米铁剂量的增加而增加，当起始pH为4．14，Cr（Ⅵ）初始浓度为10 mg／L，纳米铁投加量为30 g／L时，Cr（Ⅵ）的去除率达到95％。并对C-nZVI去除Cr（Ⅵ）的机理进行了推测，表明其涉及还原和共沉淀历程。