CapacitiveDeionizationUsingActivatedCarbonSuperCapacitorforWaterDesalination

Contact:sd14013@toyota-ti.ac.jp

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.