Zn^(2+)和HCO_3^-对纳米磁性铁去除水中砷的影响

Effect of Zn^(2+) and HCO_3^- on arsenic removal from drinking water by magnetite nanoparticles

研究Zn2+和HCO3?对纳米磁性铁去除水中砷的影响。结果表明:Zn2+可以显著增强纳米磁性铁对砷的吸附,使As(Ⅴ)去除率由原来的66%提高到99%以上;HCO3?对纳米磁性铁吸附砷具有明显的抑制作用,使As(Ⅴ)去除率降至15%;而Zn2+可以削弱HCO3?对As(Ⅴ)吸附的抑制效应,在较短时间内(2 h)去除90%以上的As(Ⅴ),达到世界卫生组织规定的饮用水砷标准10μg/L。

The effects of Zn2＋ and HCO3- on arsenic adsorption by magnetite nanoparticles were investigated.The results show that in the presence of Zn2＋,the As（Ⅴ） adsorption on magnetite nanoparticles is significantly enhanced and the arsenic removal rate is increased from 66% to over 99%;and the arsenic（Ⅴ） adsorption can be suppressed by the presence of HCO3-,resulting in the fact that the arsenic removal rate is reduced to 15%.However,the addition of Zn2＋ can offset the negative effect of bicarbonate on arsenic（Ⅴ） adsorption by magnetite nanoparticles,thus,the arsenic（Ⅴ） can be effectively removed by over 90% in 2 h,to meet the drinking water standard for arsenic（10 μg/L） set by world health organization.