Fu2019Antifoulingperformanceandmechani

ContentslistsavailableatScienceDirectJournalofMembraneSciencejournalhomepage:⁎aStateKeyLaboratoryofPollutionControlandResourceReuse,ShanghaiInstituteofPollutionControlandEcologicalSecurity,SchoolofEnvironmentalScienceandEngineering,TongjiUniversity,Shanghai200092,ChinabSchoolofChemicalScienceandEngineering,TongjiUniversity,Shanghai200092,ChinacInternationalJointResearchCenterforSustainableUrbanWaterSystem,Shanghai200092,ChinaARTICLEINFOKeywords:ElectrochemicalceramicmembraneMicrofiltrationMembranefoulingAntifoulingmechanismWastewatertreatmentABSTRACTMembranefoulingremainsasacriticalissuelimitingthewidespreadapplicationsofmembrane-basedtech-nologiesforwaterandwastewatertreatment.Inthiswork,anelectrochemicalceramicmembranereactor(ECMR),inwhichceramicmembranewithbuilt-inTimeshactedascathode/filterandTi/SnO2-Sb-Ceasanodes,wasdevelopedformitigatingmembranefoulingduringwastewatertreatment.Linearsweepvoltammetry(LSV)andelectrochemicalimpedancespectroscopy(EIS)ofTi/SnO2-Sb-Ceelectrodedemonstratedfavorableelec-trochemicalproperties.Filtrationtestswithinfluentwastewatercontaining50mg/Lsodiumalginate(SA)showedthatTMPincreaseratefortheECMRwasdecreasedby23.9–72.7%comparedtothecontrol,dependentontheexertionmodesofelectricfieldinthisreactor.ItwasfoundthatalltheoxidantscontributedtotheenhancedantifoulingperformanceoftheECMRduetoin-situmembranecleaningeffectswhilethehydrogenperoxideandactivechlorine(ClT)playedamoreimportantrolecomparedtosuperoxideanionsandhydroxylradicals.SAwasoxidizedtoasmallersizeafterreactingwithreactiveoxygenspecies(ROS)andClT,benefitingthemitigationofmembranefoulinginECMR.1.IntroductionMembranetechnologyhasbeenusedforwaterandwastewatertreatmentinrecentdecades[1–5].Nevertheless,thedeclineofpermeatefluxortheincreaseoftransmembranepressurecausedbymembranefouling(reversibleandirreversiblefouling)resultedinfre-quentmembranecleaningandmembranereplacement,limitingitswidespreadapplications[1,6].Therefore,developmentoffoulingcon-trolstrategiesishighlydesirableformembrane-basedtechnologiestreatingwaterandwastewater.Tomitigatemembranefouling,severalprotocols,suchasfabrica-tionofantifoulingmembrane[7–9],optimizationofoperatingcondi-tions[10],biological-basedstrategy(e.g.,quorumquenching)[11],andmembranecleaning[12],havebeenreported.Amoreattractivealternative,whichhasbeenproposedmorerecently,istointegrateelectrochemicaltechnologyintomembranefiltrationforcurbingmembranefoulingusingeitherexternalelectricfield[2,13,14]orin-situgeneratedbioelectricity[15].Theincorporationofelectrochemicalprocessinmembranereactorcaninducetheproductionofoxidantssuchasreactiveoxygenspecies(ROS),activechlorineandsoon,whichcouldoxidize/decomposethemembranefoulants[15–19]andcleanmembraneinsitu[20–22].Comparedtoconventionalchemicalcleaninginmembrane-basedprocesses,electrochemicalprocessensuresmembranecleaning-in-placewithoutadditionofchemicals,thusredu-cingoperationalcosts[23].However,thisprotocolsuffersfromdrawbackssuchascausingda-magetopolymericmembrane,whichiswidelyusedintheavailableliterature,duringlong-termoperationduetothepresenceofoxidants.Althoughtherehavebeenstudiesreportinginorganicmembrane(e.g.,Ti4O7membrane[24],andcarbon-basedmembranes[25]),thesefiltersmayrequirerigorouspreparationconditions(e.g.,Ti4O7membrane[26–29])orstillpoorelectrochemicalstability(e.g.,carbon-basedmembranes).Incontrast,ceramicmembranehasstrongmechanicalandchemicalstabilitytoresisttotheoxidants[30],whichcanbeoperatedunderharshconditions,thusholdinggreatpotentialtobeusedinwaterandwastewatertreatment.Therefore,developmentofelectrochemicalceramicmembranereactorforwastewatertreatmentisstillrequired.Inthisstudy,anelectrochemicalceramicmembranereactor⁎Correspondingauthorat:StateKeyLaboratoryofPollutionControlandResourceReuse,ShanghaiInstituteofPollutionControlandEcologicalSecurity,SchoolofEnvironmentalScienceandEngineering,TongjiUniversity,Shanghai200092,China.E-mailaddress:[e-mail](Z.Wang).JournalofMembraneScience570–571(2019)355–361Availableonline28October20180376-7388/©2018ElsevierB.V.Allrightsreserved.T(ECMR),inwhichceramicmembranewithbuilt-inTimeshactedascathode/filterandTi/SnO2-Sb-Ceasanodes,wasdevelopedforwaste-watertreatment.AntifoulingperformanceoftheECMRandtheme-chanismsinmitigatingmembranefoulingweresystematicallyin-vestigatedwiththeinfluentwastewatercontaining50mg/Lsodiumalginate.Interestingly,itwasobservedthattheexertionofelectricfieldindifferentmodessignificantlyaffectedtheantifoulingperformance.TheoptimizationoftheECMRoperationcould,therefore,furtherim-proveitscost-effectiveness.Theresultshighlightthatthelow-foulingECMRisanattractivealternativetobeusedforwaterandwastewatertreatment.2.Materialsandmethods2.1.ReagentsAllchemicalsusedinthisworkwereofan