纳米Fe-0作用下4-氯酚的脱氯特性及机理

纳米Fe0作用下42氯酚的脱氯特性及机理程荣1,王建龙1*,ZHANGWei_xian2(1.清华大学核能与新能源技术研究院环境技术研究室,北京100084;2.DepartmentofCivilandEnvironmentalEngineering,LehighUniversity,Bethlehem,PA1801523176,USA)摘要:采用化学还原法制备了纳米Fe0,ESEM测定结果表明其颗粒在1~100nm内.实验表明这些纳米Fe0能在20h内将初始浓度为20mgPL的42氯酚完全降解,Fe0对42CP的还原脱氯是主要去除途径.苯酚是脱氯反应的主要产物.当42CP的初始浓度由20mgPL增大到50,100,150mgPL时,其相对去除率明显降低,但绝对降解量有较大提高.温度不仅影响脱氯速率,而且影响42CP去除的途径.30e时,脱氯反应为主要反应;10e时,较易产生氧化产物.Fe原子的迁移过程在42CP的降解中也是一个重要的限速步骤.此外,纳米Fe0具有很好的稳定性,在受试的379h内,纳米Fe0能够应对不同浓度冲击及反复投加的42氯酚冲击的能力.关键词:纳米铁;42氯酚;苯酚;脱氯;地下水污染中图分类号:X70311文献标识码:A文章编号:025023301(2007)0320578206收稿日期:2006203217;修订日期:2006208208基金项目:国家自然科学基金项目(50325824)作者简介:程荣(1981~),女,博士研究生,主要研究方向为地下水污染治理,E2mail:chengrong99@mails.tsinghua.edu.cn*通讯联系人,E2mail:wangjl@tsinghua.edu.cnReductiveDechlorinationof42chlorophenolUsingNanosacleIronCHENGRong1,WANGJian2long1,ZHANGWei2xian2(1.LaboratoryofEnvironmentalTechnology,InstituteofNuclearandNewEnergyTechnology,TsinghuaUniversity,Beijing100084,China;2.DepartmentofCivilandEnvironmentalEngineering,LehighUniversity,Bethlehem,PA1801523176,USA)Abstract:NanoscaleFe0wassynthesizedthroughareductivemethodandthesizeoftheparticlesisintherangeof1~100nm,observedbyESEMimage.Theexperimentalresultsdemonstratedthatthesemetalparticlescanreduce42chlorophenol(42CP)completelyin20hours,whentheinitialconcentrationwas20mgPL.DechlorinationbyFe0isthemainreactionpathway,andphenolisthemainproduct.Astheconcentrationof42CPincreasedfrom20mgPLto50,100,150mgPL,therelativedechlorinationratiodecreasedobviously.Butthereducedamountsof42CPincreased.Temperaturecaninfluencedechlorinationrateandchangethereductivepathway.Dechlorinationisthemainreactionat30ewhilesomeoxidizedcompoundsmaybeproducedat10e.Thetransferofironatommaybeanimportantfactor,limitingthedechlorinationrate.Moreover,thestabilityanddurabilityofnanoscaleFe0wasassessedthroughbatchstudiesoverextendedperiodsoftime.TheresultsindicatedthatnanoscaleFe0canresisttheshockof42CPconcentrationduring379hours.Keywords:nanoscaleiron;42chlorophenol(42CP);phenol;dechlorination;g