利用粉煤灰制备高纯氧化铝纳米粉体的研究

12120053(,;)EarthScienceFrontiers(ChinaUniversityofGeosciences,Beijing;PekingUniversity)Vol.12No.1Mar.2005,,,,300072JIHui-ming,WUPing,ZHANGZhou,XUMing-xiaKeyLaboratoryofAdvancedCeramicsandMachiningTechnologyofMinistryofEducation;SchoolofMaterials,TianjinUniversity,Tianjin300072,ChinaJIHui-ming,WUPing,ZHANGZhou,etal.Extractinghigh-puritynano-aluminafromflyash.EarthScienceFrontiers,2005,12(1):220-224Abstract:Todaytherecycleoftheearth'sresourcesisavitalproblem,whichisofglobalinterest.Wehaveex-tractedhigh-puritynano-aluminafromcalcinedflyashusingabakingsoda(Na2CO3)method.Wehavepre-paredtheultra-finealuminumhydroxidepowdersbyaliquidchemicalmethod,andconductedresearchontheprocessesofactivation,lixiviationandcalcination,wehaveobtainedbettertechnologicalconditionsandprepar-ingparameters.Theconfiguration,structureandpurityofthesamplehavebeeninvestigatedbyXRD,TEM,BETandICP.Theresultsindicatethattheultra-finealuminumhydroxideispreparedwhentheflyashandso-daarecalcined,andpoached,andthepHofthelixiviumisaccuratelyadjusted;thatthefibriformγ-Al2O3with20～30nmindiameterand238.9m2/ginspecificsurfaceareaisobtainedwhenthealuminumhydroxideisdriedat85℃andcalcinedat800℃;andthatthesphericalα-Al2O3with30～40nmindiameterand16.82m2/ginspecificsurfaceareaisobtainedwhencalcinedat1100℃.Thepurityofthepowdersishigherthan99.9percent.Keywords:flyash;aluminumoxide;nano-powder;preparation:。(Na2CO3),。、,。XRD、TEM、BETICPAl2O3、。:、Na2CO3,pH,。85℃,800℃、1100℃2h,γ-Al2O3α-Al2O3,,238.9m2/g16.82m2/g,20～40nm,99.9%。:;;;:Tk133.1:A:10052321(2005)01022005:20041130;:20050106:(50072014):(1964-),,,,、。E-mail:[e-mail],,,Al2O3SiO2。Al2O3SiO2,[1]。,,,。Al2O3。,,,/EarthScienceFrontiers2005121221Al2O3,22%～38%,50%。,[2]。,,Al2O3,。[3],[4],[5]。、,,Park[6]。,Al2O3,,。1,1。,,。,3h,。pH,、,,1Table1Thecompositionoftheflyashusedintheexperiment/%SiO235.12Al2O353.26Fe2O32.63CaO3.41MgO0.68TiO21.96K2O0.54SO30.421.50:。pH,。,,,。Al2O3X(D/max-2500X,40kV,100mA,CuKα);(TEM,JEM-100Xd)(BET,NOVA2000);(ICP,VISTA-MPX)。22.1Al2O3,Si-Al-O。,---Si-Al-O。(Na2O,K2O,CaO,MgO)。6,。,(Na2CO3),Na2O,:Na2CO3→00Na2O+CO2(1)Na2O+SiO2→00Na2SiO3(2)Al2O3+Na2O→002NaAlO2(3)Na2CO31(2)(3)。Na2CO3,(2)(3),,,。:Na2CO3m()rm(Na2CO3)=3r2,,。2.2。HClpHAl(OH)3、。NaAlO2→00+4HClAlCl3+NaCl+2H2O(4)AlCl3+→003NaOHAl(OH)38+3NaCl(5)222,,,/EarthScienceFrontiers2005121HClNa2SiO3H2SiO3:Na2SiO3+→002HClH2SiO38+2NaCl(6)2pH[7]Table2TherangeofpHforthemetalhydroxidestodepositpH(0.10mol/L)pH(10-5mol/L)Fe(OH)31.52.8Al(OH)33.44.7、。2pH。,pHpH3Fe(OH)3,pH6.0Al(OH)3。、,,。3ICP3Al2O3Table3Thechemicalcompositionofthehighpuritynano-aluminapowders/%Al2O399.9SiO20.001Fe2O30.001CaO0.007Na2O0.015K2O0.022:。1Fig.1Therelationshipbetweennucleationorgrowthrateandtheconcentrationofthesolutionwhenpreparingpowderswithliquidphasemethod。,。2800℃2hγ-Al2O3XRDFig.2XRDpatternsofγ-Al2O3calcinedat800℃XRD,,。31100℃2hα-Al2O3k-Al2O3XRDFig.3XRDpatternsofα-Al2O3andk-Al2O3calcinedat1100℃XRD,,,,,1[8]。1.0mol/LNaOH,pH,,,/EarthScienceFrontiers2005121223,。2.3,、、。85℃,。4γ-Al2O3TEMFig.4TEMmicrographsofγ-Al2O3(140000n)TEM225、331510℃[9],,Al(OH)3,,。,,。:2Al(OH)3→00Al2O3+3H2O(7)3、710℃/min。,7℃/min。800℃,2h,XRD(2)γ-Al2O3,4,,20nm,238.9m2/g。,1100℃,2h,XRD(3),γ-Al2O3α-Al2O3k-Al2O3。TEM(5),Al2O3,30～40nm,BET16.82m2/g。3(1)Na2CO3m()rm(Na2CO3)=3r2,,HClpH,。1.0mol/LNaOHpH6.0,Al(OH)3。Al(OH)3,85℃,7℃/min,,800℃1100℃5α-Al2O3TEMFig.5TEMmicrographsofα-Al2O3(140000n)TEM2h,Al2O3。(2)XRDTEM,Al2O3γ-Al2O3α-Al2O3,20～40nm,BET238.9m2/g16.82m2/g,ICP99.9%。(3)Al2O3、、、、,。References:[1]kIANJueshi.FlyAshandFlyAshConcrete[M].Beijing:SciencePress,2001:5-65(inChinese).[2]LINJie,LIURuibin,CHENDengfu.Theprogressinthetechnologyofextractingthealuminumoxidefromtheflyash[J].ChineseJournalofProcessEngineering,2004,4(Sup-pl):271-274(inChinese).[3]LUSheng,FANGRongli,ZHAOHong.Studyofhighlypuresuper-finepowderedaluminumoxidefromflyashbywayoflimesinteredselfpowdering[J].CoalAsh,2004(1):15-17(inChinese).[4]WANGWenjing,HANZhenzuo,CHENGJianguo,etal.Thepreparingconditionsfortheextractionofaluminafromflyashbysourmethod[J].EnergyEnvironmentalProtec-224,,,/EarthScienceFrontiers2005121tion,2003,17(4):18-19,47(inChinese).[5]HUANGJieming.Experimentalstudyonaluminumandsili-conextractionfromcoalashatcommontemperature[J].E-lectricEnvironmentalProtection,2002,18:28-30(inChi-nese).[6]PARKHC,PARKYJ,STEVENSR.Synthesisofaluminafromhighpurityalumderivedfromcoalflyash[J].MaterialsScienceandEngineering,2004,367:166-170.[7]CHENkiaoying,WUXinwei,BAIYongmin.Highpurealu-minamicropowderspreparedwithneutralmethod[J].ChinaPowderScienceandTechnology,2003,8:16-18(inChi-nese).[8]WANGZhonglin,KANGZhenchuan,SUNJiashu.Func-tionalandSmartMaterials:StructuralEvolutionandStruc-tureAnalysis[M].Beijing:SciencePress,2002:220(inChi-nese).[9]ZHAOLianquan,CHUShaobin.StudyofdehydrationofAl(OH)3[J].EngineeringChemistry&Metallurgy,1991,12(3):269-271(inChinese).:[1].[M].:,2001:5-65.[2],,.[J].,2004,4():271-274.[3],,.[J].,2004(1):15-17.[4],,,.[J].,2003,17(4):18-19,47.[5].[J].,2002,18:28-30.[7],,.[J].,2003,8:16-18.[8],,.:[M].:,2002:220.[9],.Al(OH)3[J].,1991,12(3):269-271.