沸石分子筛和活性炭吸附-脱附甲苯性能对比

:,,1984,,#3(No.2007C13042)/3#(,310014)NaY(NaY)13X(13X)H(H)MCM222(MCM222)ZSM25(ZSM25)/,(AC)/,:ACNaYH13XMCM222ZSM25,:ACNaY13XHMCM222ZSM25;ZSM25,ZSM25;(1000mg/m3),NaYAC,NaY;LangmuirFreundlichRelativeperformanceofzeolitesandactivatedcarboningaseousphaseadsorptionanddesorptionoftolueneZhouChun2he,LuHanfeng,ZengLi,HuangHaifeng.(CollegeofBiologicalandEnvironmentalEngineering,ZhejiangUni2versityofTechnology,HangzhouZhejiang310014)Abstract:Therelativeperformanceoffivecommercialzeolites(NaY,ZSM25,MCM222,Hand13X)andaco2conutactivatedcarboningaseousphaseadsorption/desorptionoftoluenewasstudiedinthelab.Theobservedadsorp2tiveloadingsoftolueneonthesmalladsorberswereinthedecliningorderofACNaYH13XMCM222ZSM25.UndertheTPDconditions,theorderofthedesorptiontimewasthesameastheloadings(ACNaY,13XHMCM222ZSM25).Amongthezeolites,NaYperformedjustalittledifferentlyfromACintheadsorptionanddesorptionruns.Basedontheeffectsofinfluentflowrateandtolueneconcentrationonthebreakthroughprofiles,theadsorptionoftolueneprocesswasprimarilycontrolledbyeitherinternaldiffusion(NaY)orexternaldiffusion(ZSM25).TheloadingdatawerewellrepresentedbytheLangmuiradsorptionisothermmodel;theadsorptioncapacitieswereinfluencedlessbytolueneconcentrationatanlowconcentration.TheexperimentalresultssuggestNaYmolecu2larsievesismorefittoremovelowconcentrationVOCsfromwastegaseousstreams.Keywords:zeolites;activatedcarbon;adsorption;desorption;toluene(VOCS)[125],(),,[628],[9]249,[10,11],[12]1051,[13],,SiO2Al2O3,,[14216],VOCs,(AC),5/11.1()ACNaY(NaY)13X(13X)H(H)MCM222(MCM222)ZSM25(ZSM25)1.2ACMicro2meriticsASAP2020C,2502h(TPD)8331420094MicromeriticsAutochem2910,25mL/min,105005/min,1.31,23:1,3502h,;2;312,GC97901Fig.1Schematicdiagramoftheexperimentalsystem1;2;3;4;5;6;7;8;9;10A128089,AC1g,40,8mm50mm:q=Fc010-9Wts-ts0cic0dt(1):q,g/g;F,mL/min;t,min;c0citmin,mg/m3;W,g;ts,min22.11,MCM222,MCM222,,NaYAC,AC,NaY2.22.2.1,,5%(),,2,ACNaY2(c0=1645mg/m3,(v)=60000mL/(hg))Fig.2Breakthroughcurvesoftolueneontheadsorbents2.2.22,:ACNaYH13XMCM222ZSM25,NaY;1,,,ZHAO[12]105221053;ZSM25,ZSM250.6nm,0.6nm,ZSM25,ZSM251ACTable1Structuralpropertiesoftheadsorbents/(m2g-1)/(m2g-1)/(m2g-1)/(cm3g-1)/(cm3g-1)/nmAC935.56762.09173.470.410.300.34.4[17,18]NaY818.42762.6955.730.380.310.660.74[19]246H499.37386.73112.640.330.190.560.67[19]251225213X407.46362.7544.710.290.180.660.74[19]246MCM222413.37319.7293.650.380.160.401.82[20]ZSM25373.81289.0284.790.180.120.510.56[19]25093/2(c0=1645mg/m3,v=60000mL/(hg))Table2Adsorptiveloading,breakthroughtime,saturationtimeofthetolueneadsorptionruns/(gg-1)/(m-2)/minAC0.26871.87651018218.5NaY0.23261.85691018197.5H0.15021.96521018124.013X0.13622.18391018117.0MCM2220.10031.58531018107.0ZSM250.07791.3615101879.0,3.53681018/m22,6,AC,,,13X,NaY2.33,50,300380,:ACNaY13XHMCM222ZSM253TPDFig.3TolueneTPDprofilesoftheadsorbents1AC;2NaY;313X;4H;5MCM222;6ZSM25AC,AC[21],,;,,SiO2Al2O3(SiO2/Al2O3),,SiO2/Al2O3,,[9]250NaY13XSiO2/Al2O3(5),HMCM222ZSM25SiO2/Al2O325,NaY13X2.44,ACNaYZSM25(1000mg/m3),,[22];5001000mg/m3,ACNaY,,NaYAC,NaY4ACNaYZSM25(v=60000mL/(hg))Fig.4AdsorptiveloadingsoftolueneonAC,NaYandZSM25vs.influentconcentration2.535,ZSM25(),3000060000mL/(hg),ZSM25NaYACZSM25,,ZSM25,(),2.64,ACNaYZSM25Langmuir((2))Freundlich((3)),3qqm=kP1+kP(2)q=kfP1/n(3):qm,g/g;kLangmuir,Pa-1;P,Pa;kf04314200945ACNaYZSM25(c0=1645mg/m3)Fig.5BreakthroughcurvesoftolueneonAC,NaYandZSM25at3GHSVs3LangmuirFreundlichTable3LangmuirandFreundlichisothermsoftheexperimentaladsorptiveloadingdataLangmuirqm/(gg-1)k/Pa-1R2Freundlichkf/PannR2AC0.32340.99220.99220.10924.31440.9063NaY0.25090.39190.98670.164610.74110.9376ZSM250.08170.49170.98860.057712.90320.9662Freundlich,Pan;n,n13,AC,;LangmuirR20.98,ACNaYZSM25LangmuirFreundlich3(1)5,NaY,AC,;ZSM25,ZSM25(2)(1000mg/m3),NaYAC,NaY(3)LangmuirFreundlich:[1],.[J].,2005,24(4):40245.[2].[J].,2005,21(5):31235.[3],,.[J].,1998,20(1):427.[4],,,.Cu2Mn2O[J].,2008,30(5):26228.[5],,.[J].,2001,21(6):3242327.[6],,.[J].,2005,19(4):528.[7],,,.2[J].,1997,10(4):2182219.[8],,,.VOCs[J].,2004,22(1):36238.[9]GUILLEMOTM,MIJOINJ,MIGNARDS,etal.Volatileor2ganiccompounds(VOCs)removaloverdualfunctionaladsor2bent/catalystsystem[J].AppliedCatalysisB:Environmental,2007,75(3/4).[10]ILIYASA,ZAHEDINIAKIMH,EICM,etal.Controlofhydrocarboncold2startemissions:asearchforpotentialadsor2bents[J].MicroporousandMesoporousMaterials,2007,102(1/2/3):1712177.[11]PIRESJ,CARVAA.Adsorptionofvolatileorganiccom2poundsinYzeolitesandpillaredclays[J].MicroporousandMesoporousMaterials,2001,43(3):2772287.[12]ZHAOXS,MAQ,LUGQ.VOCremoval:comparisonofMCM241withhydrophobiczeolitesandactivatedcarbon[J].Energy&Fuels,1998,12(6).[13]SERRANODP,CALLEJAG,BOTASJA,etal.Character2izationofadsorptiveandhydrophobicpropertiesofsilicalite21,ZSM25,TS21andBetazeolitesbyTPDtechniques[J].Sep2arationandPurificationTechnology,2007,54(1):129.[14],,,.ZSM25C[J].,2004,25(8):6022606.(44)14/;0.5g/L,CODSCP3CODSCPFig.3EffectofKH2PO4concentrationonCODremovalandSCPyield2.4DO,DOSCP,,DODO,(DO),,11DOCODSCPTable1EffectofdissolvedoxygenonCODremovalandSCPyieldCOD/(mg