EDTA对微电解体系降解对硝基酚的影响李松

28　62009　　11　　　ENVIRONMENTALCHEMISTRYVol.28,No.6November2009　2009110.　＊(WTWER0719).＊＊,E-mail:[e-mail]＊李　松　刘　波　汪　琦　闫懂懂　吴文菲　陈泽智＊＊(,,,,210093)　　EDTA,,EDTA;/EDTA1000mg·l-1:120g·l-1,20g·l-1,pH3,EDTA1mmol·l-1.60min,89.7%,53.8%.EDTA,pH,/EDTA63.5%,19.5%.,,/EDTA.　,EDTA,,.　　、、,[1].,,,.,,,H2O2Fenton,[2],EDTAFe2+H2O[3]2.FeEDTAH2O2,,、、,FentonpH4.　　EDTA,EDTA,GC/MS,/EDTA,EDTA.1　1.1　　　1000mg·l-1,,、、pH,1000mg·l-1,,EDTA./EDTA(40,80,120,160,200mg·l-1)、pH(1,3,5,7)、EDTA(0.5,1,2,4,6mmol·l-1),,.1.2　　　CODGB11914-1989.COD:A%=Ct/C0×100%(C0COD;CtCOD).　　(756MC).400nm,,,:A%=Ct/C0×100%(C0,1000mg·l-1;Ct).　　pHpH;EDTA(,SPD-10AVP)[4].　　GC/MS(,9890N/5360):10ml,H2SO4784　　　　　　　　28pH2,30ml3,2ml,GC/MS.:(30m×0.25μm,0.25μm),50℃1min,8℃·min-1300℃1min,1μl.:EI,70eV,200℃.2　2.1　EDTA　　1000mg·l-1.,80g·l-1、20g·l-1、pH3.:①EDTA,EDTA2mmol·l-1,1000mg·l-1,COD、、EDTA.②2mmol·l-1EDTA,EDTA.　　1(a)(b),,COD,80min,EDTA,COD88.7%67.5%,53.8%29.4%.Fe2+[H],,EDTA,EDTA/Fe2+O2H2O2Fenton,,.,EDTA.　　1(c)(d),EDTA,,,EDTA.,EDTA,,EDTA/Fe2+O2H2O2,.,Noradoun[3]FeEDTA,EDTA、、、C3CO2、CO,C3、CO2CO35%,FentonEDTACOD,COD.1　EDTA(a)/EDTA　(b)/EDTACOD(c)EDTA　(d)/EDTAFig.1　TheeffectofEDTAonthedegradationof4-NPinmicro-electrolysissystem　6:EDTA785　　2.2　/EDTA2.2.1　/EDTA　　20g·l-1,pH3,EDTA2mmol·l-1,21000mg·l-1.40g·l-1120g·l-1,60min,60.4%84.9%.200g·l-1,76.9%.120g·l-1,,Fe2+EDTA,Fenton;,,H2O2[5],H2O2,Fe2+,H2O2,OH·,OH·OH·[6].2.2.2　pH/EDTA　　120g·l-120g·l-1,EDTA2mmol·l-1,pHpH/EDTA1000mg·l-1,3,pH3,/EDTA84.9%,,pH7,63.5%,53.8%,pH719.5%.,Fe2+,;/EDTA,EDTAFe2+,Fenton,,EDTApH.2　Fig.2　Influenceofironon4-NPdegradation3　pHFig.3　InfluenceofpHon4-NPdegradation2.2.3　EDTA/EDTA　　120g·l-1,20g·l-1,pH3,4EDTA.EDTA1mmol·l-1,89.7%,EDTA,.EDTA[FeⅡ(EDTA)(O2)]2-[3],[FeⅡ(EDTA)(O2)]2-H2O2,[FeⅡ(EDTA)(O2)]2-H2O2.,EDTA1mmol·l-1.4　EDTAFig.4　InfluenceofEDTAconcentrationon4-NPdegradation786　　　　　　　　282.3　/EDTA　　/EDTAGC/MSHPLC,、、.5/EDTAHPLC,,,,EDTA.,/EDTA,6.[H],,EDTAFenton,OH·,OH·,OH·,.5　/EDTAHPLCFig.5　TheHPLCof4-NPinmicro-electrolysis/EDTAsystem6　/EDTAFig.6　Proposeddegradationpathwayof4-NPinmicro-electrolysis/EDTAsystem3　　　(1)EDTA,EDTA,53.8%,/EDTA88.7%.　　(2)EDTApH,120g·l-1,20g·l-1,pH7,EDTA2mmol·l-1,63.5%;19.5%.　　(3)EDTA:120g·l-1,20g·l-1,pH3,EDTA1mmol·l-1,60min,89.7%.　6:EDTA787　　　　　[1]　,,,2,4-[J].,2008,27(2)∶186—189[2]　,,,FentonFenton2,4-D[J].,2005,24(4)∶365—369[3]　NoradounCE,ChengIF,EDTADegradationInducedbyOxygenActivationinaZeroValentIron/Air/WaterSysterm[J].Environ.Sci.Technol.,2005,39(18)∶7158—7163[4]　BergersPJM,DegrootAC,TheAnalysisofEDTAinWaterbyHPLC[J].WaterRes.,1994,28(3)∶639—642[5]　KavithaV,PalaniveluK,DegradationofNitrophenolsbyFentonandPhoto-FentonProcesses[J].Chemistry,2005,170∶83—95[6]　JulianaCB,MiltonDC,LadislauMNetal.,OxidationDecompositionofAtrazinebyaFenton-LikeReactioninaH2O2/FerrihydriteSystem[J].WaterResearch,2007,41∶55—62THEEFFECTOFEDTAONTHEDEGRADATIONOF4-NITROPHENOLINMICRO-ELECTROLYSISSYSTEMLISong　　LIUBo　　WANGQi　　YANDong-dong　　WUWen-fei　　CHENZe-zhi(EngineeringCenterofWaterTreatmentandEnvironmentRemediation,MinistryofEducation,NationalKeyLaboratoryofPollutionControlandResourceReuse,SchooloftheEnvironmentofNanjingUniversity,Nanjing,210093,China)ABSTRACT　　Themaindisadvantageofconventionalmicro-electrolysistreatmentisthatthedegradationefficiencyisnotveryhigh.Tosolvethisproblem,theeffectofEDTAenhancementonthedegradationof4-NPinthemicro-electrolysis/EDTAsystemwasinvestigated,duringwhichEDTAand4-NPwasdegradedbythemicro-electrolysissystem.TheresultsshowedthatEDTAcouldimprovetheremovalrateof4-NP.Theoperatingconditionsfordegradationof4-NP(1000mg·l-1)inthemicro-electrolysis/EDTAsystemwereoptimizedbyindividualfactorexperimentsandtheywereasfollowing:C(Fe)=120g·l-1,C(C)=20g·l-1,C(EDTA)=1mmol·l-1,pH=3.Underthiscondition,4-NPremovalratesreached89.7%within60min,whiletheremovalrateof4-NPwasonlyachieved53.8%bytheconventionmicro-electrolysistreatment.Themostdeservesattentionwasthatmicro-electrolysis/EDTAsystemalsodisplayedareasonablegooddegradationactivityinaneutralcondition.Theremovalof4-NPinmicro-electrolysis/EDTAsystemwasover63.5%atpHof7,whileitwasonly19.5%inmicro-electrolysissystem.Thedegradationproductsof4-NPwereidentifiedwithGC/MSmethodsandthedegradationpathwaysof4-NPwerediscussed.　　Keywords:micro-electrolysis,EDTA,effect,4-nitrophenol.