钙镁离子及重碳酸盐对零价铁还原对氯硝基苯的影响  

Effect of Ca^(2+),Mg^(2+) and HCO_3^- on the reduction of para-chloronitrobenzene by zero-valent iron

作　　者：乐晨[1] 吴锦华[1] 李平[1] 王向德[1] 杨波[2] 

机构地区：[1]华南理工大学环境科学与工程学院污染控制与生态修复广东省普通高等学校重点实验室工业聚集区污染控制与生态修复教育部重点实验室,广州510006 [2]深圳大学化学与化工学院,深圳518060

出　　处：《环境工程学报》2011年第10期2177-2180,共4页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金资助项目(50708039);国家高技术研究发展计划(863)项目(2009AA063902);中央高校基本科研业务费资助项目(2009zm0202);教育部新教师基金(20070561011);广东省自然科学基金(05300188)

摘　　要：通过间歇式实验,考察了地下水中常见硬度离子Ca2+、Mg2+及HCO3-的独立作用和联合作用对零价铁还原对氯硝基苯的影响。实验结果表明,Ca2+、Mg2+对零价铁还原对氯硝基苯反应的促进作用不明显。HCO3-浓度为0～100mg/L时可显著提高零价铁还原对氯硝基苯的速率,反应2 h后对氯硝基苯转化率由44.1%升至84.8%;当HCO 3-浓度大于100 mg/L时,促进作用会由于碳酸铁盐类物质的产生而下降。当Ca2+或Mg2+与HCO3-共存时,会产生碳酸钙或碳酸镁之类的沉淀物,占据还原位点,不利于反应的进行。当采用零价铁修复地下水氯硝基苯化合物污染时,应考虑地下水硬度的影响。Batch tests were conducted to investigate individual and cooperative effects of Ca2＋,Mg2＋ and HCO-3 in groundwater on the reduction of para-chloronitrobenzene（p-CNB） by zero-valent iron（ZVI）.The results showed that Ca2＋ and Mg2＋ did not improve p-CNB reduction.HCO-3 significantly enhanced p-CNB conversion rate when its concentration was 0～100 mg/L;p-CNB removal increased from 44.1% to 84.8% in 2 h.But p-CNB removal efficiency decreased owing to the formation of ferric carbonates when HCO-3 concentration exceeded 100 mg/L.Due to the formation of CaCO3（or MgCO3） blocking the active sites where electron transfer took place,the coexistence of Ca2＋（or Mg2＋） and HCO-3had an inhibitory effect on p-CNB removal.It indicated that the effects of hardness and bicarbonate in groundwater should be taken into account when zero-valent iron is applied for the remediation of chloronitrobenzenes contaminated groundwater.

关 键 词：地下水 硬度 零价铁 对氯硝基苯 

分 类 号：X703[环境科学与工程—环境工程]