纳米零价铁去除垃圾渗滤液中铬(Ⅵ)的性能及机理研究  

BATCH REMOVAL EFFICIECY OF Cr(Ⅵ) FROM LANDFILL LEACHATES BY NANO ZERO-VALENT IRON AND ITS MECHANISM

作　　者：柳听义[1] 赵林[1,2] 谭欣[1,2] 刘涉江[1] 黄宇[1] 齐云[1] 毛国柱[1] 

机构地区：[1]天津大学环境科学与工程学院,天津300072 [2]天津大学化工学院,天津300072

出　　处：《环境化学》2010年第3期429-433,共5页Environmental Chemistry

基　　金：国家自然科学基金(批准号:20776096)资助

摘　　要：利用柠檬酸处理后的纳米零价铁(NZVI)对铬(Cr(Ⅵ))的去除进行了研究.NZVI对Cr(Ⅵ)的去除率受Cr(Ⅵ)初始浓度、pH值、反应温度和NZVI的浓度等因素影响,在Cr(Ⅵ)初始浓度为20mg.l-1、pH=5.0、NZVI投加量为1.0g.l-1和20℃条件下,Cr(Ⅵ)去处率达到了100%.腐殖酸(HA)与Cr(Ⅵ)可以形成稳定的HA-Cr螯合物,这种螯合物减少了溶液中有效的Cr(Ⅵ)浓度;同时,HA与NZVI的反应减少了NZVI的有效活性位点,HA的存在对NZVI去除Cr(Ⅵ)有竞争抑制的作用.Nanoscale zero-valent iron（NZVI）with an mean size of 62.5 nm was pretreated with citric acid and used to remove Cr（Ⅵ）.The results indicated that factors such as initial concentrations of Cr（Ⅵ）and NZVI,pH,and temperature,played a prominent role on removal rates.With an initial Cr（Ⅵ）concentration of 20 mg·l-1,NZVI dose of 1.0 g·l-1,pH 5 and a temperature of 20℃,removal rate reached 100%.HA chelates iron ions or oxide surface,and reduces the available Cr（Ⅵ）in the solution and the rate of Cr（Ⅵ）removal.Furthermore,HA reacted with NZVI and reduced reactive sites of NZVI available to Cr（Ⅵ）.So HA adversely affected Cr（Ⅵ）removal using NZVI in the leachates.

关 键 词：纳米零价铁 腐殖酸 柠檬酸 铬(Ⅵ) 螯合物 

分 类 号：X703[环境科学与工程—环境工程]