高盐废水残余Ca的离子交换软化实验张弦

478Vol.47No.820188THERMALPOWERGENERATIONAug.20182017-12-30(51602228)SupportedbyNationalNaturalScienceFoundationofChina(51602228)(1989—)[e-mail](II)430072Ca(II)AmberliteIRC747LetwatitTP260D1133Ca(II)3Ca(II)LangmuirFreundlichIRC747TP260D11381.4375.08109.17mg/gCa(II)IRC747D113TP260∆Go∆Ho∆SoEa3Ca(II)Ca(II)X703ADOI10.19666/j.rlfd.201712166,,,.Ca(II)[J].,2018,47(8):66-72.ZHANGXian,YEChunsong,HUANGJianwei,etal.SofteningexperimentonionexchangeofresidualCa(II)fromhighsalinitywastewater[J].ThermalPowerGeneration,2018,47(8):66-72.SofteningexperimentonionexchangeofresidualCa(II)fromhighsalinitywastewaterZHANGXian,YEChunsong,HUANGJianwei,LIUTong(SchoolofPowerandMechanicalEngineering,WuhanUniversity,Wuhan430072,China)Abstract:Duringtheprocessofconcentrationandminimizationofhighsalinitywastwater,residualCa(II)easilyformscalciumcarbonateandcalciumsulfateprecipitates,whichaffectsthelong-termstableoperationofthemembraneconcentrationsystem.Inthisstudy,theadsorptionmechanismofresidualCa(II)fromhighsalinitywastwaterbyAmberliteIRC747ionexchangeresin,LetwatitTP260ionexchangeresinandD113ionexchangeresinisstudiedbystaticadsorptionsystem.Theresultsshowthat,theadsorptioncapacitiesofthreeionexchangeresinsincreasesasthecontacttimeisprolongedandthereactiontemperatureisincreased,whileincreasingthesaltcontentprohibitstheadsorptionofCa(II).Besides,LangmuirisothermsarefittedbetterthanFreundlichisotherms,andthetheoreticalmaximumadsorptioncapacitiesofIRC747,TP260andD113are81.43mg/g,75.08mg/gand109.17mg/g,respectively.TheadsorptionofCa(II)byionexchangeresinsisinaccordancewiththepseudo-second-orderkinetics,theorderofinitialreactionrateisIRC747D113TP260.Inaddition,thethermodynamicparameterssuchasGibbsfreeenergychange(∆Go),enthalpychange(∆Ho),entropychange(∆So)andactivationenergy(Ea)oftheionexchangereactionrevealsthattheadsorptionofCa(II)bythesethreeionexchangeresinsiseffective,endothermicandspontaneous.Keywords:highsalinitywastewater,ionexchangeresin,Ca(II),staticadsorptionmethod,isotherms,kinetics,thermodynamics[1-2]8Ca(II)67[3][4][5]-Ca(II)[6][7][8]Yu[9]AmberliteIRC748Ca(II)Ca(II)47.21mg/gYi[10]AmberliteIRC747Ca(II)Ca(II)Ca(II)11.1AmberliteIRC747Rohn&HaasLewatitTP260LanxessD113311Table1FundamentalpropertiesoftheionexchangeresinsIRC747TP260D113/(meq·g-1)6.615.019.32/mm0.50~0.650.40~1.250.32~1.25/8080100pH1.5~14.01~124~141mol/LNaOHD113ARARARMettlerToledoAL204COS-110X30101ThermoOrion230A+pHHannaHI98351.21.2.1Ca(II)2:1Ca(II)100mg/L35g/L0.1g250mL100mL298.15K3691530456090120180240360480600720minCa(II)(1)Ca(II)[11]0()ttCCVqm(1)qtCa(II)mg/gC0Ca(II)mg/LCtCa(II)mg/LVLmgCt=Ceqt=qeCeqeCa(II)(mg/L)(mg/g)1.2.2Ca(II)Ca(II)100mg/L35g/L0.1g250mL100mL298.15303.15308.15313.15318.15KCa(II)1.2.3Ca(II)6Ca(II)100mg/L35567798119140g/L(24NaClNaSO:2:1mm)0.1g250mL100mL298.15K682018(II)1.2.435g/L(24NaClNaSO:2:1mm)Ca(II)40~250mg/L0.1g250mL100mLCa(II)298.15KCa(II)303.15308.15313.15318.15K1.2.50.1g250mL100mL35g/L298.15K3691530456090120180240360480600720minCa(II)303.15308.15313.15318.15K22.11Ca(II)1Ca(II)C0100mg/L298.15KFig.1EffectofcontacttimeonadsorptioncapacityofCa(II)byionexchangeresins(C0=100mg/Landthereactiontemperatureis298.15K)130min3Ca(II)Ca(II)Ca(II)[10]480minCa(II)3Ca(II)IRC747(68.8mg/g)D113(64.0mg/g)TP260(58.5mg/g)2.2kdedeqkC(2)qeCa(II)mg/gCeCa(II)mg/L223Ca(II)2C0=100mg/LFig.2Effectofreactiontemperatureonequilibriumdistributioncoefficientofionexchangeresins(C0=100mg/L)2.33Ca(II)33Ca(II)35g/LIRC747TP260D1138Ca(II)69(II)71.660.366.5mg/g140g/L3Ca(II)55.443.639.2mg/g22.6%27.7%41.0%3Ca(II)C0100mg/L298.15KFig.3EffectofsalinityonadsorptioncapacityofCa(II)byionexchangeresins(C0=100mg/Landreactiontemperatureis298.15K)Ca(II)D113[12]2.4LangmuirFreundlichTemkinScatchardLangmuir[13]eee001CCqQQb(3)Q0mg/gbL/gFreundlich[14]efeloglog(1/)logqknC(4)kfFreundlichnFreundlichLangmuirFreundlich3Ca(II)45245LangmuirCa(II)IRC747TP260D1130.9990.9970.995Langmuir4Ca(II)Langmuir298.15KFig.4LangmuirisothermsofCa(II)fromhighsalinitywastewaterbyionexchangeresins(reactiontemperatureis298.15K)5Ca(II)Freundlich298.15KFig.5FreundlichisothermsofCa(II)fromhighsalinitywastewaterbyionexchangeresins(reactiontemperatureis298.15K)2LangmuirFreundlichCa(II)Table2EquationparametersoftheCa(II)adsorptionbyionexchangeresinsfittedbyLangmuirandFreundlichisothermsLangmuirFreundlichQ0/(mg·g-1)b/(L·mg-1)R2kfnR2IRC74781.430.210.99933.165.290.934TP26075.080.100.99725.344.710.986D113109.170.040.99514.882.580.987LangmuirRL[15]702018(5)C0Ca(II)mg/LbLangmuirRL1RL=1RL1RL=0[16]RLCa(II)C066RL016Ca(II)298.15KFig.6VariationsofseparationfactorwithinitialCa(II)concentration(reactiontemperatureis298.15K)2.5Elovich[17]ee1ln()lntqqqkt(6)qeqttmg/gk1min-1[18]22ee1tttqkqq(7)k2g/(mg·min-1)22ehkq(8)2expcal2cal()qqq(9)qexpqcalmg/g783Ca(II)3Ca(II)IRC747TP260D1130.9970.9920.99571.7463.4165.70mg/g71.660.366.5mg/gCa(II)7Ca(II)C0=100mg/L298.15KFig.7Pseudo-first-orderkineticsfittingtheadsorptionofCa(II