[ Objective ] The aim was to research the effects of Cr( Ⅵ ) and the factors of removing dissolved Cr( Ⅵ ) with nanoscale zero valent iron. [ Method ] With Cr ( Ⅵ ) as the material, nanoscale zero-valent iron was synthesized in aqueous solutions by reduction of Fe3＋ with NaBH4. The effects on removal ratio were analysed under the initial concentration of Cr ( Ⅵ ) were 10.0、20.0、30.0、50.0、70.0 mg/L, temperatures were 15、20、25、30、40 ℃ , the pH were 3、5、7、8、9 for the NZVI dosage were 0. 01、0. 03 、0. 04 、0. 05 、0. 07 g. [ Result ] Cr( Ⅵ ) could be removed effectively with NZVI and the removal ratio was more than 90％ with an initial pH of 5 at 25 ℃, and 0. 05g/100 ml NZVI when the Cr( Ⅵ ) concentration was 20.0 mg/L. [ Conclusion ] Cr ( Ⅵ ) could be removed by NZVI, the pH, Cr ( Ⅵ ) initial concentration,temperature and the NZVI dosage were the main factors of effecting Cr( Ⅵ ) removal.%[目的]研究纳米零价铁(NZⅥ)对水中Cr(Ⅵ)的脱除效果及影响Cr(Ⅵ)脱除的主要因素.[方法]以Cr(Ⅵ)为研究对象,采用NaBH液相还原Fe制备纳米级零价铁(NZVI),分析了0.01、0.03、0.04、0.05、0.07 g的NZVI对初始浓度为10.0、20.0、30.0、50.0、70.0 mg/L,温度分别为15、20、25、30、40℃,pH分别为3、5、7、8、9条件下的Cr(Ⅵ)去除率的影响.[结果]纳米零价铁可在极低投加量下有效去除溶液中Cr(Ⅵ),在25℃、pH为5、常压、恒温振荡器转速200 r/min、NZVI加入量0.05 g/100 ml的条件下,水体中20 mg/LCr(Ⅵ)的去除率大于90%.[结论]纳米零价铁能快速去除水体中Cr(Ⅵ),溶液pH,Cr(Ⅵ)初始浓度,温度,投加量等是影响Cr(Ⅵ)脱除的主要因素.
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