简介:Theadsorptionofproteinonnanoparticleswasstudiedbyusingdynamiclightscatteringtomeasurethehydrodynamicsizeofbothpureproteinandnanoparticlesadsorbedwithdifferentamountsofprotein.Thethicknessoftheadsorbedproteinlayerincreasesasproteinconcentration,butdecreasesastheinitialsizeofnanoparticles.Afterproperlyscalingthethicknesswiththeinitialdiameter,weareabletofitallexperimentaldatawithasinglemastercurve.Ourexperimentalresultssuggestthattheadsorbedproteinsformamonolayeronthenanoparticlesurfaceandtheadsorbedproteinmoleculesareattachedtotheparticlesurfaceatmanypointsthroughapossiblehydrogen-bonding.Ourresultsalsoindicatethatasproteinconcentrationincreases,theoverallshapeoftheadsorbedproteinmoleculecontinuouslychangesfromaflatlayerontheparticlesurfacetoastretchedcoilextendedintowater.Duringthechange,thehydrodynamicvolumeoftheadsorbedproteinincreaseslinearlywithproteinconcentration.
简介:Theadsorptionofxenonfromairhasaninterestinthemonitoringofnuclearexplosionoraccident,orinthetreatmentofnuclearwastegas.Inthispaper,theporestructureofseveralseriesofactivatedcarbonfibershasbeencharacterized.Theadsorptionpropertiesofxenonontheseactivatedcarbonfibersunderdifferenttemperatureshavebeenstudiedindetails.Theresultsshowthatthexenonadsorptionamountonactivatedcarbonfibersdonotincreasewithspecificsurfaceareaofadsorbents,butarecloselyrelatedtotheirporesizedistribution.Poreswhoseradiusequaltoornarrowthan0.4nmwouldbemoreadvantageoustotheadsorptionofxenon.
简介:Inthispaper,theselectiveadsorptionofLDLonchitosanmodifiedwithPEGandAsp.wasstudied.TheadsorptionrateofLDLandHDLonthedoublemodifiedchitosanwas57%and12%respoectively,TheresultsshownthatthedoublemodifiedchitosancanbeusedaadsorbentforselectivebindingtoLDL,thisworkmayhelptodevelopfunctionalcolumnsforhemoperfusion.
简介:StructuresofaseriesofactivatedcarbonfibersweremodifiedbyimpregnatingthemwithorganicandinorganicmaterialssuchasMethyleneblue(Mb)、p-nitrophenol(PNP)、NaClorbyoxidizingwithKMnO4orHNO3.Theinfluenceofporefillingorchemicaltreatmentontheirxenonadsorptionpropertieswasstudied.TheexperimentalresultsshowthatMbandPNPfillingofactivatedcarbonfibersresultinthedecreaseofxenonadsorptioncapacitiesofthesetreatedACFs,whichisduetothedecreaseoftheirsurfaceareaandmicro-porevolume.However,theadsorptioncapacityincreasesgreatlywithoxidizingtreatmentofactivatedcarbonfibersby7mol/LHNO3.
简介:Investigationoftheadsorptioncharacteristicsoftolueneontwohypercrosslinkedresins.Thestaticandthekineticadsorptionwerestudied.Theequilibriumadsorptiondatewasfittedtofreundlichadsorptionisothermmodelstoevaluatethemodelparameters.Theenthalpy,freeenergy,entropyareindicativeofanexothermic,aspontaneousanddisorterdecreasingprocess.ExperimentalresultsshowthatthetwoadsorbentsarebetterthantheAmberliteXAD-4forremovingthetolueneinaqueoussolutions.
简介:Bothinorganicandorganicpillaredmontmorilloniteswereusedtoadsorbphenol.BatchkineticsandisothermstudieswerecarriedouttoevaluatetheeffectofequilibriumtimeandpHonadsorptionofphenolbymontmorillouitesandre-adsorbingcharacteristicsofpillaredmontmorillonites.TheadsorptionofphenolincreasedwithincreasingsolutionpHvalues.Theeliminationratioofphenolfromthesolutionbytheabsorptionoforganicmodifiedpillaredmontmorillonite(OrPMt)reachedequilibriumquicklyaftervibratingfor5minutes.Meanwhilefororganicmontmorillonite(OrMt),pillaredmontmorillouite(PMt)andmontmorillonite(Mt),thetimetoreachphenol-absorptionequilibriumwere20,30and90minutes,respectively.Theadsorbingcapacityofthepillaredmontmorillonitemodifiedwithsurfactantimprovedgreatly.Thephenol-adsorbingcapacityofpillaredmontmorillonitesmainlydependedonmicroporousstructureandsurfacecomponentofthemodifiedclays.Aftercalcinationat500℃,thepillarstructureandthebasalspacing(1.83nm)werestillstable.Sothepillaredmontmorillonitecouldberecycled,anditwasapotentialmaterialforadsorbingenvironmentalpollutants.
简介:Theadsorptionbehaviorofdyesonavarietyofsisalbasedactivatedcarbonfibers(SACF)hasbeenstudiedinthispaper.TheresultsshowthatthiskindofACFhasexcellentadsorptioncapacitiesforsomeorganic(dye)molecules.SACFcanremovenearlyallmethyleneblue,crystalviolet,bromophenolblueandEriochromeblueblackRfromwaterafterstaticadsorptionfor24h.at30℃.Theadsorptionamountscanreachmorethan400mg/gwhenadding50mgSACFinto50mldyesolution.Underthesameconditions,theadsorptionamountsofxylenolorangefluoresceinandEriochromeblackTwreelower.Ontheotherhand,theadsorptionamountschangealongwiththecharacteristicsofadsorbents.TheSACFsactivatedabove840℃,whichhavehigherspecificsurfaceareasandwiderporeradii,havehigheradsorptionamountsforthedyes.TheresearchingresultsalsoshowthattheadsorptionratesofdyesontoSACFsdecreasebytheorderofmethyleneblue,EriochromeblueblackRandcrystalviolet.
简介:Severalmacroporouspolymericadsorbents(NDA-999,XAD-8,X-5andXAD-2)wereemployedinthestudytoadsorbphenylaceticacidfromaqueoussolution.EffectofsaltandambienttemperatureonadsorptionwasstudiedusingNDA-999adsorbentandtheadsorptionprocessconformstoFreundlich'smodelreasonably.Adsorptiondynamicswereconductedinbatchexperimentsinordertomakeclearthemechanismofadsorptionprocess.Itisprovedthatthesquareddrivingforcemasstransfermodelcanbeadoptedtoelucidatetheprocess.Thetreatmentprocessofindustrialwastewatercontaininghighstrengthofphenylaceticacidwasproposedforcleanerproductionofphenylaceticacid.
简介:Theadsorptionofphenolandnitrophenolsonhypercrosslinkedpolymericadsorbentwasstudiedasafunctionofthesolutionconcentrationandtemperature.Adsorptionisothermsofphenolandnitrophenolsonhypercrosslinkedresinweredetermined.TheseisothermsweremodeledaccordingtotheFreundlichadsorptionisotherm.TheisothermsforphenolandnitrophenolsonhypercrosslinkedresinwereassignedasLcurves.Thermodynamicparameterswerecalculatedforallphenolandnitrophenols.Thekineticsexperimentresultsshowedthattheadsorptionrateswereofthefirst-orderkinetics.Therateconstantsat303Kwerecalculated.
简介:Inthispaper,benzeneadsorptionisothermandtheirhysteresisontwoimportantlocaldiatomitesweredeterminedat25℃,andtheirsiliconhydroxylgroup(SiOH)numberwasdetermined,theirpropertieswerereported,andtherelationshipbetweensurfacestructure,surfaceSiOHnumberpernm2andadsorptionisothermwithhysteresiswasdiscussed.Thespecificsurfacewasalsocalculatedfromtheisotherms,andpore-sizedistributionwasdetermined.
简介:Theisothermaladsorptionofdyesonavarietyofsisalbasedactivatedcarbonfibers(SACFs),andtheinfluenceofpHandtemperatureonadsorptionarediscussedinthispaper.Theresultsindicatethattheadsorptionofmethyleneblue,crystalvioletandEriochromeblueblackRonSACFsshowstypeIisothermsandcanbedescribedbytheLangmuirequationortheFreudlichequation.Theacidityofsolutionhasgreatlyinfluenceovertheadsorptionamountsofmethyleneblue,crystalvioletandEriochromeblueblackR.AspHsofthesolutionswereadjustedtoincreaseordecreasefromtheoriginalacidityofthesolution(4.7,4.1and4.0formethyleneblue,crystalvioletandEriochromeblueblackR,respectively),theamountsofdyesadsorbedonSACFsincreased.Theadsorptiontemperature(intherangeof25-50℃)exertslittleinfluenceontheadsorptionamountofmethyleneblue,crystalvioletandfluorescein.Forazodyes(EriochromeblueblackRandEriochromeblackT),however,theadsorptionamountincreasesslightlywiththeelevationoftemperature.
简介:Theadsorptionkineticsandmechanismofanovelchelateresin,macroporousphosphonicacidresin(PAR)forIn(III)wereinvestigated.Thestaticallysaturatedadsorptioncapacityis216mg·g-1resinat298KinHAc-NaAcmedium.Theapparentadsorptionrateconstantisk298=4.84×10-5s-1.TheadsorptionbehaviorofPARforIn(III)obeystheFreundlichisotherm.Thethermodynamicadsorptionparameters,enthalpychange△H,freeenergychange△Gandentropychange△SofPARforIn(III)are11.5kJ/mol,-12.6kJ/moland80.8J/mol·K,respectively.TheapparentactivationenergyisEa=3.5kJ/mol.ThemolarcoordinationratioofthefunctionalgroupofPARtoIn(III)isabout3∶1.
简介:TheinteractionsbetweenmetalionssuchasZn2+,Pb2+,Mn2+,Hg2+,Cd2+,Ni2+andchitosanhavebeeninvestigatedusingthemodelclustermodelmethodanddensityfunctionalmethod.FulloptimizationandfrequencyanalysisofallclustermodelshavebeenperformedemployingB3LYPhybridmethodat3-21Gbasissetlevelexceptmetalionswhichwereinvokedtouseeffectivecorepotential(ECP)method.Theenergychanges,andthemainstructuralparametershavebeenobtainedduringthetheoreticalstudyoftheadsorptionofmetalionsonthechitosan.Thecalculationsshowedthatthecoordinationmodesofmetalionswithchitosanmodelsweredifferent,thegeometriesofMn2+,Zn2+,Cd2+,Hg2+,Pb2+ionscoordinatedwithtwonitrogenatomsandtwooxygenatomsweredistortedtetrahedral,whilethesquareplanarstructureofNi2+coordinatedtwonitrogenatomsandtwooxygenatomswasobserved.Theheatofreactionbetweensixmetalionsandchitosanmodelsshowedtheorder:Mn2+>Ni2+>Zn2+>Pb2+>Hg2+>Cd2+,thissuggestedthatthecoordinationstrengthofMn2+>Ni2+>Zn2+>Pb2+>Hg2+>Cd2+.
简介:Thesorptionbehaviorandmechanismofanovelchelateresin,diglycolamidicacidresin(DAAR),forSm(lll)wereinvestigated.TheoptimalsorptionconditionofDAARforSm(lll)ispH=6.0inHAc-NaAcmedium.Thestaticallysaturatedsorptioncapacityis190mg/gresinat298K.TheSm(lll)adsorbedonDAARcanbeelutedreaching100%by0.5-2.0mol/LHCIusedaseluant.Theresincanberegeneratedandreusedwithoutapparentdecreaseofsorptioncapacity.Theapparentsorptionrateconstantisk298=1.96×10^-5s^-1.Theapparentactivationenergyis26kJ/mol.ThesorptionbehaviorofDAARforSm(lll)obeystheFreundlichisotherm.Thethermodynamicsorptionparameters,enthalpychangeΔHofDAARforSm(lll)is16.9Kl/mol.ThemolarcoordinationratioofthefunctionalgroupofDAARtoSin(111)is3.ThesorptionmechanismofDAARforSm(lll)wasexaminedbyusingchemicalmethodandIRspectrometry.ThecoordinationbondwasformedbetweenoxygenatomsinthefunctionalgroupofDAARandSin(Ill).
简介:ANEXPERIMENTALSTUDYONTHEHEPARIN-FREEHEMODIALYSISOFHEMOPHANADSORPTIONANEXPERIMENTALSTUDYONTHEHEPARIN-FREEHEMODIALYSISOFHEMOPHA...