二氧化锰与钴离子协同活化PMS降解AO7的效能研究

二氧化锰与钴离子协同活化PMS降解AO7的效能研究Title:SynergisticActivationofPotassiumMonopersulfatebyManganeseDioxideandCobaltIonsfortheDegradationofAcidOrange7Abstract:Thesynergisticactivationofpotassiummonopersulfate(PMS)bymanganesedioxide(MnO2)andcobaltions(Co2+)forthedegradationofAcidOrange7(AO7)wasinvestigatedinthisstudy.ThedegradationefficiencyofAO7wasevaluatedunderdifferentexperimentalconditions,includingthedosageofMnO2,Co2+,andPMS,initialpH,andreactiontime.TheresultsdemonstratedthatthecoexistenceofMnO2andCo2+significantlyenhancedthePMSactivationprocessandledtoimproveddegradationofAO7.TheoptimalconditionsforthesynergisticactivationofPMSbyMnO2andCo2+werefoundtobeaMnO2dosageof1.0g/L,aCo2+dosageof10mg/L,aPMSdosageof0.10mmol/L,pH4.0,andareactiontimeof60min.Undertheseconditions,thedegradationefficiencyofAO7reached98.6%.ThemechanismofthesynergisticeffectbetweenMnO2andCo2+wasproposedbasedonthegenerationofreactiveoxygenspeciesandtheirinteractionswithAO7.Keywords:potassiummonopersulfate,manganesedioxide,cobaltions,synergisticactivation,AcidOrange71.IntroductionAcidOrange7(AO7)isawidelyusedazodyethatiscommonlyfoundinindustrialwastewater,suchastextiledyeingandprintingindustryeffluents.AO7hasbeenlistedasaprioritypollutantduetoitspotentialtoxicity,persistence,andenvironmentalimpact.Therefore,thedevelopmentofeffectivemethodsforthedegradationofAO7isofgreatimportance.Advancedoxidationprocesses(AOPs)haveshownsignificantpotentialinthetreatmentoforganicpollutants,includingdyes,duetotheirabilitytogeneratehighlyreactiveoxygenspecies(ROS)thatcaneffectivelydegradepollutants.AmongvariousAOPs,theactivationofpotassiummonopersulfate(PMS)hasgainedattentionduetoitshighoxidizingpowerandenvironmentalcompatibility.However,theefficiencyofPMSactivationforAO7degradationneedstobeimproved.2.MaterialsandMethods2.1MaterialsThematerialsusedinthisstudyincludepotassiummonopersulfate(PMS),manganesedioxide(MnO2),cobaltchloride(CoCl2),andAcidOrange7(AO7).Allchemicalswereofanalyticalgrade.2.2ExperimentalProcedureTheexperimentswerecarriedoutinbatchreactorsunderambientconditions.ThedegradationofAO7wasevaluatedbymonitoringthechangesinabsorbanceatthemaximumwavelengthofAO7(484nm)usingaUV-Visspectrophotometer.Theeffectofdifferentexperimentalparameters,suchasMnO2dosage,Co2+dosage,PMSdosage,pH,andreactiontime,wasinvestigated.3.ResultsandDiscussion3.1EffectofMnO2DosageThedegradationefficiencyofAO7increasedwithincreasingMnO2dosageupto1.0g/L.FurtherincreaseinMnO2dosagedidnotsignificantlyenhancethedegradationefficiency.3.2EffectofCo2+DosageTheadditionofCo2+improvedthedegradationefficiencyofAO7.TheoptimumCo2+dosagewasfoundtobe10mg/L.3.3EffectofPMSDosageThedegradationefficiencyofAO7increasedwithincreasingPMSdosageupto0.10mmol/L.ExcessivePMSdosagedidnotshowasignificantimprovementinthedegradationefficiency.3.4EffectofpHThepHofthesolutionhadasignificantimpactonthedegradationefficiency.ThehighestdegradationefficiencywasachievedatpH4.0.3.5EffectofReactionTimeThedegradationefficiencyofAO7increasedwithincreasingreactiontimeupto60min.After60min,thedegradationefficiencyremainedconstant.4.MechanismofSynergisticActivationThesynergisticeffectbetweenMnO2andCo2+canbeattributedtothegenerationofROSfromthereactionbetweenMnO2andPMS,aswellasthecatalyticroleofCo2+inpromotingthegenerationofROS.ThegeneratedROSwereresponsibleforthedegradationofAO7.5.ConclusionInthisstudy,thesynergisticactivationofPMSbyMnO2andCo2+forthedegradationofAO7wasinvestigated.Theoptimalconditionsforthesynergisticeffectweredetermined.TheresultsshowedthatthecoexistenceofMnO2andCo2+significantlyenhancedthedegradationefficiencyofAO7.TheproposedmechanismofthesynergisticeffectwasbasedonthegenerationofROSandtheirinteractionswithAO7.Thefindingsofthisstudyprovidevaluableinsightsintothedevelopmentofefficientmethodologiesforthetreatmentofdye-containingwastewater.References: