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Extraction

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Extraction

    Extraction

Apr.2008,Volume2,No.4(SerialNo.5)JournalofChemistryandChemicalEngineering,ISS

    N1934-7375,USA

    ;ExtractionofsamariumbyNaOLpentanol-hetpane--NaNO3

    ;winsorIImicroemulsionsystems

    ;KONGFan.ting2XIAChuanbo1.

    ;YANGYanzhaoi.XINXuemei

    ;I1.SchoolofChemist~.andChemicalEngineering,ShandongUniversity,Jinan25010~C

    hina;

    ;2.JinanChemicalFertilizerPlantCo.,Ltd,Jinan250101,China) ;Abstract:Theinfluenceoftheconcentrationofsodiumoleate ;(NaOL)andpentanolonthewateruptakeofmicroemulsionwas ;stuied.TheeffectoftheconcentractionofNaOLandpentanoJ ;ontheextractionyieldofsamariumwasinvestjgated.Theresult ;showsthattheextractionandcOncentrajOnofsamariumis

    ;effectiveunderwelldefinedconditionsutilizingWinsorll ;microemulsioinsystems.TheFTIRspectraandconductivity

    ;researchmayindicatethatstablehydrophobicchelate ;complexeswereproducedaftertheextractionofSin(il1)by ;NaOLmicromulsionsystems.

    ;Keywords:microemulsion;extraction;sodiumoleate; ;samarium

    ;1.Introduction

    ;Microemulsionsareclear,stable,isotropicliquid ;mixturesofoil,waterandsurfactant,frequentlyin ;combinationwithacosurfactant,whichusuallyare ;shortormediumchainlengthalcoho1.Winsor

    ;classifiedthemicroemulsionsystemsintothreetypes: ;oilinwater(O/W)inequilibriumwithoil,waterinoil ;(w/o)inequilibriumwithwater,andbicontinuous ;(o+W)’inequilibriumwithoilandwater.These

    ;systemsarealsocalledWinsorI,IIandIIIsystems ;respectively.TheW/Omicroemulsionwithaqueous ;phase(Winsror?systems1issurfactantaggregatesin

    ;anapolarsolventinwhichthesurfactantspolarheads ;aredirectedtowardthecoleoftheaggregatewhereas ;thehydrophobictailsaredirectedoutward,shielding ;theinnerpolarcorefromtheapolarmedium.

    ;‘Acknowledgments:ThisworkwassupportedbytheNature

    ;ScienceFoundationofShandongProvince(No.Y2007B05).

;Correspondingauthor:YANGYanzhao,

    ;male,Ph.D.,

    ;professor;researchfields:separationandpurification ;technology,materialschemistry.Email:yzhyang@sdu.edu.cn. ;8

    ;WinsrorIIsystemcanbeusedfortheextraction ;ofmetalions.Becauseofitsuniquepropertiesas ;separationmediasuchasthenanometersizedspherical

    ;orbicontinuousstructure,therapidcoalescenceand ;reseparationdynamicsofthestructureandthe ;enhancedsolubilizationcapacity,theextractionof ;metalionsinaqueousphasewithW/Omicroemulsion ;organicphase(WinsorIIsystem)isoftenvery ;effectivefortheaccelerationofextractionaswel1asfor ;theimprovementofextractability.

    ;Therehavebeenlotsofimportantresearches ;relatetomicroemulsionextraction.BrejzaEVand ;PelezdeortizESstudiedtheextractionofAl(m,and ;Zn(II)withtwoW/Omicroemulsions,onecontaining ;DEHPA.TheyfoundthattheextractionofAI(III)with ;theDEHPAmicroemulsionincreasedgreatlywith ;respecttothatintheconventionalDEHPAsystem, ;whelestheextractionofZnwaslowerthanthatinthe ;singleDEHPAsystem.Extractionwiththe

    ;DEHPAfreemicroemulsionwasverylow.showing. ;thatmetalionsolubilizationwasnotimportantinthe ;mechanisrriofmicroemulsionextractiont.F.Kubom ;etcutili.zedcalyx(4)arenesolubilizedinAOTreversed ;micellarsolutionfortheextractionofrareearthmetals ;(EuandY)andtheirseparationfromZn.The

    ;extractionandtheseparationofmetalswasvery ;excellent.Theyalsoinvestigatedtheextractionof ;metalsbyAOTmicellarsolutionwithoutanextractant, ;andfoundthatthedegreeoftheextractionofeach ;metaldecreasedwiththeincreaseinthesodiumion ;concentrationbecausethejnteractionbetweenthe ;ExtractionofsamariumbyNaOL..pentanol-.hetpane..NAN03wlnsorIImlcroemuislons

    ystems

    ;anionheadgroupofA0Tandsodiumcationblocksthe ;extractionofothermetalions.Theextractionof

    ;galliumandaluminumwasstudiedinmicroemulsified ;systemsusingsaponifiedcoconutoilandKelex100as

    ;surfactants.Theextractionbymicroemulsionproved ;tobemoreefficientthanconventiona1solvent

;extraction[4.

    ;TheextractionofcobaltfromNH4SCN

    ;aqueoussolutionsbyCTMABmicroemulsionsystems ;wasreported.Theextractionyieldwasabove93% ;undercertainconditions

    ;Thepurposeofthisworkistoinvestigatethe ;possibilityofsamariumextractionandconcentration ;bvWinsorIIsystems.Theinfluencefactorsonthe ;extractionyieldandtheextractionmechanismare ;investigated.

    ;2.Experimentalprocedures

    ;2.1Instruments

    ;Thevibrator(YanchengScienceInstrument ;Factroy,JiangsuProvince),withavibrationfrequency ;of275~5min’andatemperaturecontrollingprecision

    ;Of?1K.UV754Spectrophotometer(Shanghai

    ;Precision&ScientificInstrumentCo..Ltd).CL2

    ;magneticstirringapparatus(YuhuaInstrumentFactory, ;HenanProvince).DDS307typedigitalelectric

    ;conductivitymeterfShanghaiPrecision&Scientific

    37CM1FFIR ;InstrumentCo.,Ltd).Brock7500

    ;spectrophotometer.

    ;2.2Materiais

    ;Sodiumoleate(AR,ShanghaiFirstReagent ;Factory),npentanol(AR,BeijingYiliReagent ;Factory),nheptane(AR,TianjinDamaoReagent ;Factory),ArsenszoIII(AR,BeijingChangping ;ShanyingChemicalPlant),SamariumOxide(AR, ;SinopharmChemicalReagentCO.,Ltd),Sodium ;nitrate(AR,TianjinKaitongReagentFactory). ;Allaqueoussolutionswerepreparedusing ;distilledwater.

    ;2.3Experimentalmethods

    ;TheaqueousSmsolution(feedsolution)was ;preparedbyadding8m203toHNO3solutionandthe ;pHwasadjustedwithHNO3andNaOH.Inthe

    ;followingstudies,theinitialSm(III)concentrationis ;2.7x10mol/L,thepHofthefeedsolutionis1.3and ;theconcentrationofNaNO3infeedsolutionis0.5 ;mogLunlessstatedspecially.TheadditionofNaNO3 ;tothefeedsolutionwastopreventemulsificationinthe ;extractionprocess.

    ;Inordertopreparemicroemulsion,

    ;surfactant--pentanol??heptanewasmixedincertain

    ;proportionandthoroughlystirred.Thesolubilityof ;surfactantsolidswasverypoorinthemixture.soitwas ;turbidatthebeginning.Tbenthewaterwasaddedinto ;themixtureuntiltheturbidsolutionjustturnedclear ;andcontinuedwhilethesolutionjustturnedturbid ;again.Theweightofthewateraddedwasrecorded,and ;itisthemaximumwateruptakeofthemicroemulsion ;system.

    ;Allextractionswereconductedin100cmglass ;containerduringagitation.Thefeedphase,consistedof ;Sm,

    ;HNO3andNaNO3wasfirstplacedinbottomof ;thecontainer.Microemulsion,preparedintheabove ;method,wasaddedonthetopofthefeedsolutionand ;meanwhilethevibratorwerestarted.Thetwophases ;wereshakedmechanicallyfor6minutestoreach ;equalization.Themixturewasmaintainedatrestuntil ;thetwophaseseparatedcompletely.

    ;Thesamariumconcentrationinaqueoussolutions ;wasmeasuredbymeansofspectrophotometrat652nm ;andtheconcentrationinmicroemulsionphasewas ;calculatedbymassbalance.

    ;Alloftheexperimentswereperformedat302K, ;unlessstatedspecially.Wedefine:

    ;E%=×100%

    ;WhereE%isthe

    ;samarium(III),moandmt

    ;samarium(Il1)ionsinfeed

    ;respectively.

    ;extractionyieldofthe

    ;arethetotalamountof

    ;solutionsatt=0andt=t,

    ;9

    ;ExtractionofsamariumbyNaOL?pentano|hetpane-NaN03winsorIImicroemulsion ;

    ;sy

    ;ste

    ;

    ;m

    ;

    ;s

    ;3.ResulIsanddiscussion

    ;3.1Wateruptakeofthemicroemulsion

    ;AsiSwellknown,themassoftheaqueous

    ;internalphaseisaveryimportantparameterwhich ;determinesthemicroemulsioncapacityforextraction. ;Therefore.inthefirstseriesofexperiments,thewater ;uptakeofthemicroemulsionwasinvestigatedasa ;functionoftheconcentrationofNaOLandpentano1. ;3.1.1EffectofNaOLconcentration

    ;Thewateruptakeofmicroemulsionasafunction ;ofsurfactantconcentrationwasinvestigatedwith ;n-pentanoiascosurfactant,andtheresultwasshownin ;Fig.1.

    ;FromFig.1WCcanseethatthewateruptakeof

    ;mircoemulsion(W%)increasedasastraightline ;basicallywiththeincreaseoftheNaOLconcentration. ;w%

    ;Fig.1EffectofNaOLconcentration(w%)

    ;onwateruptakew%,pentano1)=40%

    ;3.1.2EffectofpentanolcOncentractiOn

    ;Cosurfactants,whichusuallyareashortor

    ;mediumchainlengthalcohol,canscreentherepulsive ;forcesbetweenthechargedsurfactantheadgroups,and ;thusenhancetheaggregationofthesurfactant ;molecules.Thewateruptakeofmicroemulsionasa ;functionofconcentrationofpentanolwasstudied.The ;resultwasshowninFig.2.

    ;10

    ;?

    ;w%

    ;Fig.2Effectofpentanolconcentration(w%) ;onwatercontent;W%(NaOL)=8%

    ;AsshowninFig.2.withtheincreaseofthe

    ;pentanolconcentration,thewatercontentof ;microemulsionfW%)firstincreasedtoamaximum ;andthendecreasedsharply,withasubsequentslow ;decreasetoaflatform.ThisiSbecause:

    ;Increasingthealcoholconcentrationcanincrease ;thealcoholpartitioningattheinterface,and ;consequentlyincreasethetotalinterfacialareafor ;sOlubi1izatiOn.Thiswillcontributetoanincreasein ;solubilization.However,atsufficientlyhighalcohol ;concentration.thefluidityoftheinterfaceincreaseto ;theextentthatattractiveinterdropletinteractionstarts ;dominatingthesystem,andhencethesolubilization ;decreases.

    ;3.2Extractionofsamariumbymicroemulsion

    ;3.2.IEffectofsodiumoleateconcentrationonE% ;TheeffectofNaOLcOncentratiOnOf

    ;microemulsiononextractionyield(E%)wasstudied. ;TheobtainedresultwasshowninFig.3. ;AsisshowninFig.3,,withtheconcentration ;increaseofsodiumoleate,theCffFVCofsamarium ;extractionyieldexhibitsamodestincreaseinitially,

    ;followedadrasticincrease,andageneralincreaseat ;last.

    ;o/o^

    ;Extractionofsamarium

    ;

    ;byNaOL-pentanol-het

    ;

    ;pane-NaNO3winsorIImicroemulsionsystems ;1.1.1

    ;6O

    ;3O

    ;0

    ;0.080.120.160.200.24

    ;C?oL/mOI/L

    ;Fig.3EffectofNaOLconcentration

    ;ontheextractionyieldofSm(1I1)

    ;Note:V%(pentano1)=20%.R=8.

    ;3.2.2EffectofpentanolconcentrationonE% ;Theeffectofpentanolconcentrationof ;microemulsiononextractionyield(E%1wasstudied. ;TheobtainedresultwasshowninFig.4. ;81

    ;78

    ;75

    ;72

    ;1015202fi3035

    ;C/w.pentano

    ;Fig.4Effectofpentanoiconcentration ;ontheextractionyieldofSmUII)

    ;Note:C.NaOL:O.20mol/L.R:8.

    ;InFig.4,theextractionyield(E%)curves ;increasedwiththeincreaseofpentanolconcentration ;firstandthenreduced.ThereisamaximumofE% ;whenV%(pentano1)iSaround20%.

    ;3.2.3TheFTIRspectraandelectricconductivity ;study

    ;Theexperiment(a)whichcanbeseeninTable1

    ;wasperformedtogaintheloadsaturationorganic ;phaseofSmandexperiment(b)wasperformedfora ;comparativestudy.Theloadsaturationorganicphase ;gainedfromexperiment(b)wasWinsorII

    ;microemulsionabsolutely.

    ;Table1Saturatedextractionexperiments

    IRspectraoftheloadsaturationorganic ;TheFr

    ;phaseweremeasured.TheresultwasshowninFig.5. ;(a)

    ;(b)

    ;Fig?5TheFT-IRspectraofloadsaturationorganicphase ;OntheFrIRspectraofWinsorIImicroemulsion ;phase(Fig.5b),wecanfindthestretchingvibration ;bandofH2Oat3413.83cm-anddeformationvibration ;bandat1637.83cm,respectively,whichconfirmed ;theexistenceofwaterinmicroemulsion.The ;ll

    pentanol?hetpane??NaNO3winsorIImicroemulsi;ExtractionofsamariumbyNaOL--

    onsystems

    ;asymmetricalstretchingvibrationbandofCOOisat ;1559.87cm,andtheintensityincreaseofthisbandis ;attributedtothegreatermolarextinctioncoefficient ;resultingfromwiderelectroncloudspreadingand ;greaterdipolemomentofthehydratedpolargroupsf6J. ;Thebandat1405.77cmisthesymmetricalstretching ;vibrationbandofC00..

    ;InFig.5a,thevibrationbandofHzOcannotbe ;found,andtheasymmetricalstretchingvibrationband ;ofCOOat1550.6cm,canbefoundwithnothe

    ;intensityincrease.Thismayindicatethereisnowater ;intheloadsaturationorganicphaseofSm”.Theband

    ;at17l1.5cmistheasymmetricalstretchingvibration ;ofCoOH.becausetherearealittleHinthefeed ;solutionofSm”andreactedwithOLtoproducesome

    ;oleicacidintheextractionprocess.

    ;Moreover,inFig.5a,thesymmetricalstretching ;vibrationbandofCOOaround1410cmcanaJmost

    ;notbefound,whichmayindicatethattheionpair

    ;compoundNaoL’havebeenchangedtooleateswith

    ;chelatestructure.

    ;Theelectricconductivity(6)oftheloadsaturation ;organicphasewasmeasured.Theresultwasgivenin ;Table2.

    ;Theorganicphaseaftertheextractionexperiment

    ;(b)wasW/Omicroemulsion,soweearlseethatithasa ;comparativehighelectricconductivityofO.85ps/cmin ;Table2.Wealsocanseethatthe1oadsaturation ;organicphaseofSm”werealmostnotelectric.Soitis

    ;possiblethatitwasnotamicroemulsionbutapure ;organicphase.

    ;Table2Theelectricconductivity(6)of

    ;Loadsaturationorganicphase

    ;4.Conclusions

    ;Ithiswork.theextractionofsamariumfroma ;weakacidicfeedsolutionwasstudiedbyNaOL ;microemulsion.Someconclusionscouldbedrawn ;fromtheresultsobtainedinthisstudy:

    ;12

    ;‘I.heextracUonofsamariumbyNaOL

    ;microemolsinisveryefficient.Theextractionyield ;(E%)isnearly100%whenR=8,CNaOL=0.24moUL ;andV%fpentano1)=20%.

    ;Thereisanoptimalconcentractionofalcohol ;(20%,v/vo)inmicroemulsionfortheextractionof ;samarium.

    ;AftertheinvestigationofFr_IRspectraand ;electricconductivitymeasurementoftheload ;saturationorganicphaseofSm,weinferredthatthe ;extractionofSmwithNaOLmicroemulsionmaybe ;anionexchangereactionwithNainsodiumoleate. ;Thereactionproductisastablehydrophobicchelate ;complexofmetalionsandOL..Inaddition.thischelate ;complex,withnosurfaceactivitytoforma

    ;microemulsion,dissolvesinthecontinuousorganic ;phase.

    ;References:

    ;1P.AWinsor.SolventPropertiesofAmphhilic ;Compounds.Butterworth.London,1954.

    ;2E.V.Brejza,E.S.PerezdeOrtiz.Phenomenaaffectingthe ;equilibriumofAl(1l1)andZn(I1)extractionwithWinsorII ;microemulsions.J.ColloidInterfaceScL.2000,227: ;244.246.

    ;3F.Kubota,K.Shinohara,K.Shimojo,T.Oshima,M. ;Goto.S.Fumsaki.T.Hano.Extractionofraremetalsby ;calyx(4)arenesolubilizedinAOTreversedmicellar ;solution.Sep.PurifTechno1..2oo1.24:93-l0o. ;I41T.N.deCastroDantas,M.H.deLucenaNeto,A.A.Dantas ;Neto.Galliumextractionbymicroemulsions.Talanta,

;2002.510891097.

    ;51ZHUT.,YANGY.Z.ExtractionofcobaltbyCTMAB- ;pentanolheptane.HClWinsorIImicroemulsionsystems. ;J.RadioanaLNuc1.Chem..20O6,267:401-406. ;61WUJ.G.,SHlN.,ZH0UW.J.,ZHoUN.F.,GAOH.C., ;XUG.X.Extractionandsurfacechemistry(I)-Microscop- ;icinterfaciaJphenomenainsolventextraction.Progressin ;NaturalScience,1997.7:257.

    ;(EditedbyHubertandSam)

    ;

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