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CapacitiveDeionizationUsingActivatedCarbonSuperCapacitorforWaterDesalination
Contact:[email protected]
Yunong Wang1,2,3,JunKim3,4 ,QilinLi3,41MaterialsScienceandEngineering,DepartmentofAdvancedScienceandTechnology,ToyotatechnologicalInstitute,
2Nakatani-RIES:ResearchandInternationalExperienceforStudentFellowship,RiceUniversity,3DepartmentofCivilandEnvironmentEngineering,RiceUniversity,4Nanosystems EngineeringResearchCenterforNanotechnology-EnabledWaterTreatment(NEWT)
Inordertoincreasethefreshwatersupply,capacitivedeionization(CDI) technologyhasbeenidentifiedasapromisingenergy-efficientdesalinationtechnologyremovingsaltsfromaqueoussolutions.
・Thisresearchprojectwasconductedaspartofthe2016Nakatani RIESFellowshipforJapaneseStudentswithfundingfromtheNakatani Foundation.Formoreinformation,pleasevisithttp://nakatani-ries.rice.edu/.・IwouldliketothankDr.Qilin Li,JunKim,andPeiDongforalloftheirhelponthisresearchproject.SpecialthanksalsotoProfessorKono,SarahPhillips,Shimada-san,Ogawa-san,Endo-san,andTakarada-sanformakingthisprogrampossibleandforalloftheirsupport.
Quantificationofions
Flow-throughmicro-conductivitysensorICP-OES
Electrosorption test
Flow-bydesalinationtest
Materialcharacterization
Contactanglemeasurement Cyclicvoltametry (potentiostat)
・ThecarbonelectrodeishydrophobicevenafterEthanolwashed.・CDIsystemcanremovesaltfromwaterefficiently.・Theelectorsorption isareversible process.・TheregenerationcanbeachievedbydischargingActivatedCarbonelectrodes.
SAC(mg/g)
ASAC(mg/g/min)
MSAR(mg/g/min)
NaCl 4.57 0.27 0.38NaCl+CaCl2 1.75 0.11 0.21
・ThebasicmechanismofCDI1
1. R.Zhou,P.M.Biesheuvel,andA.vanderWal,Energy&EnvironmentalScience,vol.5,2012.
2. C.H.Hou,C.Y.Huang,C.Y.Hu,Applicationofcapacitivedeionizationtechnologytotheremovalofsodiumchloridefromaqueoussolutions,vol.10:753-756,2013.
Electrosorption experiment
・Desalinationtestatconstantvoltage1.2V.・Currentusedforelectrosorption waswithin0.005Arange.・Moresaltwasremoved(intermsofconductivity)onmono(Naonly)solutionwasusedasfeed.
・Samplesaretakenbyeach3minutesfromthe3rdcycle.#TheabsorptionofNa+ionsisfollowingtheelectrosorption /regenerationcycles.
Na
#Electrosorption /regenerationcycleformixturefeedwatercostsmoretimethanNaCl solution.#Na+ andCa2+ ionsarenotdistinctivelyreducedmuchduringtheadsorptionperiod.
Cyclicvoltametry (two-electrodes)Contactanglemeasurement(hydrophobic)
・Modifiedexperimentmethodtoidentifytime-dependention-selectivityandregenerationprocess.・Applyinghighercapacitancecarbonnano-materialsfortheCDIelectrodes.