360 likes | 388 Views
Carbon based materials : a promising approach for water depollution by electrochemical advanced oxidation processes. Prof. Marc CRETIN, European Membranes Institute, University of Montpellier, France http://www.iemm.univ-montp2.fr/
E N D
Carbonbasedmaterials: apromisingapproachforwaterdepollutionbyelectrochemicaladvancedoxidationprocesses Prof.MarcCRETIN, EuropeanMembranesInstitute,UniversityofMontpellier,France http://www.iemm.univ-montp2.fr/ Theme:EmergingTechnologiesandApplicationsofDiamondandCarbonMaterials Int.Conf.onDiamondandCarbonMaterials July17-18,2017Chicago,Illinois,USA
Outline PartA:ElectrodematerialsforElectrochemicalAdvancedOxidationProcesses forpollutantsmineralization Environment Energy PartB:CouplingenergyconversionandEAOPforFuelCellFentonsystem
PharmaceuticalsinEnvironmentand RemediationTechniques 3
Pharmaceuticalsinenvironment Householdsewage: excretedandexpireddrugs Livestockandaqua farming Groundwater WWTPs effluents Surfacewater Pharmaceuticalindustries Hospitalswaste 1
Environmentimpacts Toxiccompounds: Bio-accumulableandstableintheenvironment Abnormalphysiologicalprocesses/Increaseincidenceofcancer(Kolpinetal.,2002) Developmentofantibioticresistantpathogens(Bartelt-Huntetal.2011) Reproductiveimpairmentinaquaticorganisms(Bartelt-Huntetal.2011) Specificcases DeclineofvulturepopulationinIndiain1990s(Oaksetal.,2003) AppearancesColiinGerm in2011 (Ratolaetal., 5
RemediationTechniques Emerging pollutants Treatments Physico- chemical Advanced Oxidation Processes (AOP) Biodegradation Pollutants transfer but no degradation ! Need of secondary treatments ! Pollutants: Mineralization in CO, HOand 2 2 potentially in small organic acids • Some compounds are toxic for micro- organisms • MembraneBioreactor • Adsorption, • Coagulation,Flocculation • MembraneSeparation • BiologicalOxidation 6
Advancedoxidationprocess(AOP) Basedontheoxidativepotential(thermodynamicapproach) andthereactivitypower(kineticapproach)ofOHradicals OH: Thermodynamic E°=2.80V/SHE OH: Kinetic . Productsk=109-1010 M-1s-1 S+OH NONselectiveoxidantwithhighkineticconstants 7
RemediationTechniques WaterTreatments Advanced Oxidation Processes (AOP) Pollutants: Mineralization in CO2, H2O and potentially in small organic acids OH°:NONselectiveoxidant withhighkineticconstants OH:Kinetic Ratedegradationk=109-1010M-1s-1 OH:Thermodynamic E° = 2.80 V/SHE 8
Advancedoxidationprocesses(AOP) BasicallyradicalscanbeproductedbytheFentonreaction: . +H2O+OH H2O2+Fe2++H+ Fe3+ MainDrawbacks: • High quantityofchemicalsis needed(Hydrogenperoxide) • Sludges formation(basedon Fe(OH)3precipitation) 9
HowtoproduceOH°radicalswithoutchemicals? Indirectlybyelectro-Fentonprocessbasedon:electrochemicalreductionofdissolvedO2: O22H2eH2O2 AndbytheFentonreaction: Fe2H H O Fe3H O OH 2 2 2 Ongraphitecarbonelectrodelike: CarboŶ Felt ;CFͿ or ŵodified CF… Directlybyelectrochemical wateroxidation: H OOHHe 2 Onelectrodewithhighoxygenover-potentiallike: borondopeddiamond,TiOx;x<2Ϳ… 10
Selectedpharmaceuticalsandazodye Amoxicillin Propanolol Paracetamol AcidorangeII
Radicalsproductionbycathodicelectro-Fentonprocess GraphenetoenhanceperformancesofCathodicMaterials Exfoliation Grapheneoxideparticles ElectrophoreticdepositiononCF 2-Dlayerofone-atomthicksheetcomposedofsp2carbonatomsarrangedinahoneycombstructure GrapheneoxideonCF 2DstructureofgrapheneCharacterizedbyXRDandAFM Electrochemicalor thermalreduction ReducedGrapheneoxideonCF Leetal.RSCAdv.,2015,5,42536-42539
ReducedGrapheneoxidetoenhanceperformances XPSanalysis RawCF=rawcarbonfeltGO=grapheneoxideTR=Thermallyreduced • RawCF: • Smoothsurface-89.9° HighefficiencyofGOThermalreduction(N2/5%H2)ofGO • Thermalreduction OpenporesfilledupbyrGO-0°
ReducedGrapheneoxidetoenhanceperformances Electrochemicalbehaviorsofmodifiedelectrodes CV-Redoxprobe[Fe(CN)6]3–/[Fe(CN)6]4– EIS-Nyquistplots Highelectrochemicalresponseandlowinterfacialresistanceofreducedgrapheneoxideobtainedeitherbyelectrochemicalorthermalreduction O2reductionintoH2O2 Fe2HHOFe3HOOH 2 2 2 LinearscaninpresenceofdissolvedO2
ReducedGrapheneoxidetoenhanceperformances AO7solutionaftera 5’ treatment RemovalofanazodyebyElectron-Fenton Apparentfirstorderrateconstantsandabatementsforthedegradationkineticsof AO7 Abatement(%)after3 min kapp(min-1) R2 Cathode rawCF 0.2596 0.9961 54.2 rGO-CF 0.7846 0.9987 81.4 TOCremovalafter2h.treatment Highmineralization(95%after8h.)Highstability
ToworkatlargepHwindow(pH3–7)without • intrant(i.e.pHadjustmentandferricsolution) Heterogeneouselectro-Fentonprocess:aneffectivealternative • Surfacecatalyzedprocess– expandpHwindow • Highrecyclabilityandreusability Advantages -Catalystaddedinthesolution Configuration/Design Catalystloaded/impregnatedintheelectrode-cathode Nopost-treatmentseparation CoFe-LDHcoatingforelectro-FentonatcircumneutralpH
CoFe-LDHcoating Synthesis:Solvothermalprocess Co(NO3)2.6H2O+Fe(NO3)3.9H2O+CO(NH2)2+NH4F CoFe-LDH/CF Hydrothermaltreatment Growthsolution Autoclave Optimumconditions-90oC,7hand 2:1(Co:Fe) Av.loading=7.0 ± 0.3mgcm‒2 17
CoFe-LDHcoating Characterizationofthepreparedelectrode SEManalysis 50 µm 50 µm Rawcarbon-felt LDHCoatingonCFaftersolvothermaltreatment:Ursineslikestructure 10 µm Magnifiedimage 18
CoFe-LDHcoating Comparisonbetweenheterogeneousandhomogeneoussystem Heterogeneouscatalyst 100 CoFeLDH Co+Fe2:1 80 Homogeneouscatalyst Co+Fe1:1 TOCremoval(%) 60 Fe HeterogeneousSurface-catalyzedprocesspredominantatcircumneutralpH 40 20 HomogenouscatalyzedprocessDecreasesatcircumneutralpH 0 3 5,83 pH 7,1 • highermineralizationwithCoFe-LDH/CFcomparedtohomogeneous • systematalltimeandpH • LowefficiencyinhomogeneousEFaspHincrease– catalystprecipitation 19
? Electro-Fentonprocess ThiXuan HuongLe,M. Cretinetal.Journal ofMaterialsChemistryA, 2016, 4, 17686-17693 « Coverpicture»
? Electro-Fentonprocess ThiXuan HuongLeetal. Journal ofMaterialsChemistryA, 2016, 4,17686-17693 « Coverpicture»
Fuelcells Electro-Fentonprocess ThiXuan HuongLeetal. Journal ofMaterialsChemistryA, 2016, 4,17686-17693 « Coverpicture»
FuelCell-Fentonsystem e- e- Cathode Anode e- EFprocess e- Carbonfelt(CF) Au@CF Toproposetheproofofconceptforanautonomoussystemforwaterremediationassociatingnanoparticlesforglucoseoxidationandcarbonbased catalystforoxygenreduction
Anodicelectrode (Au@CF) 1) Electro-deposition of gold layers on rawCF by cyclic voltammetry (CV) in solution containing chloroauric acid 10 µm 10 µm 1000°C,60’ N2 2)Thermaltreatment 333 nm 50 µm 1.5 µm
FuelCell-Fentonsystem 15 10mM glucose -Glucos 12,5 CF@Au e 3 2 10 F-Glucos j/mAcm-2 rawC e 7,5 Carbonfelt(CF) 5 2,5 1 0 -2,5 -5 Anode e- e- Cathode -0,8-0,6-0,4-0,200,20,40,60,81 E/Vvs.Ag/AgCl e- EFprocess Au@CF for glucose oxidation e- ? Au@CF
Cathodic electrode (?) ElectrocatalyticpropertiesofrawCFarenotadaptedto getspontaneousreactionwhenassociatedwithAu@CF NeedtoincreaseO2reductionpotentialbythedeposit ofamicroporouslayerofN-dopedC
Cathodic electrode (CF@pC) SynthesisofporouscarbonbyALD/solvothermalgrowthofMOFonCF • Zn • OZnOfilmdepositedat100°C • Growth rate0.2 nm/cycle Zn(C2H5) H2O 2 1) ALD of ZnO on carbon felt substrate c)Exposureto H2O b) Purge with Ar d)PurgewithAr a) Exposure to diethyl zinc ZIF-8 Pores Autoclaveat100°C, 5hwith2-methyl-imidazole 2) Solvothermal conversion of ZnO in ZIF-8 Zinc-Nitrogen tetrahedra 1000 °C,10h pC@CF Porous carbon layer deposited on carbon felt EvaporationofZinc in ZIF-8 structure 3) Carbonization of Carbon felt/ ZIF-8 Under nitrogen 200mL/min
Cathodic electrode (CF@pC) Characterization VolumetryGasAdsorptionofN2: XPS • Raw-CF:0.0915m²/g • CF-pC:64m²/g(porevolume=0.082 cm2/g)→700timeshigher Contact angle measurements of water drop Sampleraw-CFpC@CFAngle(°)89.9 0 Polarizationcurves Propertie HydrophobHydrophilic ic Positive shift for ORR (0.4V) O2+2H++2e-→ H2O2
FuelCell-Fentonsystem e- e- e- EFprocess e- pC@CF Au@CF • Au@CF anode presents electrocatalytic properties for glucose oxidation • pC@CF cathodepresents electrocatalytic properties for O2 reduction into H2O2
Fuel Cell-Fentonsystem Durabilityofthecellforthedecoloration quantifiedbyabsat485nm AO7degradation(quantifiedbyHPLC) Acid orange 7 Week 0 Good reproducibility and durability Main results Decolorization of the solution after a few hours Electricalperformanceofthe FC-Fentoncell UVvisiblespectra Degradation of the aromatic formed as subproducts after 24h ThiXuan HuongLeetal. Journal ofMaterialsChemistryA, 2016, 4, 17686-17693
Conclusions ImprovementofcarbonmaterialspropertiesforElectrocatalysis inEnvironnementalApplications Clean technology: Electrochemical Advanced Oxidation Process Green energy: Biomass & Fuel cell electro-Fentonprocess + Fuelcells Carbonfeltmodifiedby N-dopedmicroporouscarbon and/orreducedGrapheneOxide CarbonfeltmodifiedbyGoldNanoparticles FuelCellFentonsystem
Worksinprogress Worksinprogress -CathodicN-dopedmicroporouscarbonlayerstooptimizepollutantsadsorptionandelectrochemicaldegradationbyEF AppliedCatalysisandInterfaces2017,M.Cretinetal. TheJournalofPhysicoChemistry2017,M.Cretinetal. -CathodicelectrocatalyticNPdepositedoncarbonfelttooptimizeoxygen reductionforenergysaving(fuelcells,microbialfuelcells,enzymaticfuelcellsforwaterdepollution) -AnodicnanomaterialstoimproveanodicoxidationofbiomasstoreplacegoldNPdepositedoncarbonfelts BimetallicNPforbiosourcedfueloxidation (glycerol,ethanol…)
Worksinprogress Worksinprogress -Reactivecarbontubularmembranesforelectro-Fentoncoupledwith pressure-drivenprocesses Increaseofthedegradationkineticof60%forTMP>2barbyincreasingmasstransfer P Retentate Permeate O2 H2O2 H2O +CO2 MarcCretinetal.,JournalofMembraneScience510(2016)182–190 H2O Alimentation OH° (effluent) +organicpollutants WE CE (Eouicontrôle)
Worksinprogress -Sub-stoichiometricTiO2Magnéliphaseasapromisingreactiveelectrochemicalmembrane(REM)forelectrooxidation Patented Poresize:1.5to2µmPorevolume:30to45% Patented Ti4O7thinfilmdepositedonTisubstrate • AnodeperformancesTi4O7>BDD>Pt>DSA WaterResearch Vol.106 2016, M.Cretinetal. Degradationkineticofanantibiotic(amoxicilline) asafuntionoftheanodematerial
Acknowledgments Manythanksto ….Mika, Sophie T. , Huong,Martin, Anne,SophieC.,Yaovi,Widya,Roseline,Clément,Christel,Mehmet,Clémence,Gauthier, Stella, Eddy…… TheANRFRENCHPROGRAMCELECTRON2014-2018 forelectrochemicaladvancedoxidationprocessesforwastewatertreatment
Thankyouforyour attention!