Fe/Zn双金属对地下水中PCBs的还原脱氯研究

Study on Reductive Dechlorination of PCBs in Groundwater by Fe/Zn Bimetal

[目的]研究Fe/Zn双金属对地下水中PCBs的还原脱氯效果。[方法]以Fe、Zn构建二元金属还原体系,以PCBs降解率为考察指标,研究了添加羟丙基-β-环糊精(HP-β-CD)时,Fe/Zn双金属对PCBs的降解效果,同时考察了负载率、金属投加量对PCBs脱氯的影响。[结果]合成的HP-β-CD对PCBs有很好的增溶作用,PCBs表观溶解度随HP-β-CD浓度增加而线性增加,形成1∶1的包结物;10℃下,当混合金属投加量为10 g,Zn质量分数为7%时,321μg/L PCBs降解7 d后的去除率为47.6%。[结论]该研究为PCBs污染的地下水原位修复提供了理论指导。

[ Objective ] The research aimed to study reductive dechlorination effect of PCBs in groundwater by Fe/Zn bimetal. [ Method ] Fe/ Zn bimetal as reduction system, PCBs degradation ratio as inspected index, degradation effect of PCBs by Fe/Zn bimetallic system when adding self-made hydroxypropyl-β-cyclodextrin （HP-β-CD） was studied. Meanwhile, we investigated the influences of loading ratio and Fe-Zn dosage on the dechlorination of PCBs. [ Result] PCBs was significantly solubilized by the synthesized HP-β-CD. With increase of the HP-β-CD concentration,the apparent solubility of PCBs increased linearly,forming 1：1 inclusion complex. When Fe-Zn dosage was 10 g, and mass fraction of Zn was 7% ,the dechlorination efficiency of PCBs with 321 ug/L was 47.6% after degrading for 7 d at 10 ℃. [ Conclusion] The research provided theoretical guiding for in situ remediation of the groundwater contaminated by PCBs.