La2O3和CeO2的制备及催化臭氧氧化对氯硝基苯

41　420094　　　　　　　　　JOURNALOFHARBININSTITUTEOFTECHNOLOGY　Vol.41No.4Apr.2009　　　　　　La2O3CeO2叶苗苗,陈忠林,沈吉敏,贲　岳,徐贞贞(,,150090,[e-mail])　:为提高单独臭氧氧化去除水中有机污染的能力,分别以La(NO3)3·6H2O和Ce(NO3)3·6H2O为前驱体,采用水解沉淀法制备La2O3和CeO2粉体,利用X射线衍射、N2吸附、扫描电镜以及红外光谱分析技术对样品的晶相结构、粒径大小、比表面积、孔容、孔径分布以及表面官能团等进行表征.以蒸馏水配制的对氯硝基苯溶液(pCNB)为目标物,考察La2O3和CeO2的催化臭氧氧化活性.结果表明,La2O3和CeO2对pCNB的吸附作用有限,20min的吸附率分别为6.7%和9.9%.臭氧对pCNB的去除能力有限,反应20min的去除率仅为37.2%,以La2O3为催化剂时,去除效果有明显增加,反应20min时去除率为82.1%,而以CeO2为催化剂时,去除效果反而没有O3单独氧化效果好,20min时的去除率仅为24.3%.:催化臭氧氧化;氧化镧;氧化铈;对氯硝基苯:X703.1:A:0367-6234(2009)04-0077-04Synthesisoflanthanumoxideandceriumoxideandozonationcatalyticactivitiesofp-chloronitrobenzeneYEMiao-miao,CHENZhong-lin,SHENJi-min,BENYue,XUZhen-zhen(StateKeyLaboratoryofUrbanWaterResourceandEnvironment,SchoolofMunicipalandEnvironmentalEngineering,HarbinInstituteofTechnology,Harbin150090,China,[e-mail])Abstract:Toimprovetheefficiencyofozonationforremovaloforganicpollutionfromwater,lanthanumoxideandceriumoxidewerepreparedascatalystsforthecatalyticozonationbyhydrolysisofLa(NO3)3·6H2OandCe(NO3)3·6H2O,respectively.Thephysicochemicalfeaturesincludingcrystallitephases,crystallitesize,BETsurfacearea,totalporevolumeandfunctionalgroupsofthecatalystswerecharacterizedbyXRD,N2adsorption,SEMandFTIRspectrumanalysis.Theozonationcatalyticactivitiesoflanthanumoxideandce-riumoxideweretestedbycatalyticozonationoftracep-chloronitrobenzene(pCNB)inwater.TheresultsshowedthattheadsorptionratesofpCNBbylanthanumoxideandceriumoxidein20minwere6.7%and9.9%,respectively.TheremovalrateofpCNBbyozonealoneinthereactionfor20minwasonly37.2%.TheremovalrateofpCNBwassignificantlyincreasedbyaddinglanthanumoxideasthecatalyst,andthepCNBremovalrateof82.1%wasobtainedafterthereactionfor20min,whilethepCNBremovalof24.3%wasob-tainedafterthereactionfor20minbyusingceriumoxideasthecatalyst.Keywords:catalyticozonation;lanthanumoxide;ceriumoxide;p-chloronitrobenzene:2007-11-13.:(2007AA06Z339);(50578052;50821001).:(1981—),,;(1967—),,,.　　,.,、、;,.,,O3H2O2、UV、,———[1].,O3/.,Fe2O3、TiO2、CeO2、MnO2、CuO[2-6].CeO2La2O3,、、[7,8],CeO2La2O3.(pCNB)[9,10],,,pCNB.La(NO3)3·6H2OCe(NO3)3·6H2O,La2O3CeO2,pCNB,La2O3CeO2.1　实　验1.1　La2O3CeO2La(NO3)3·6H2OCe(NO3)3·6H2O,pH7.8,12h,,800℃400℃4h,La2O3CeO2.1.2　La2O3CeO2D/max-rBX-,XCuKα(λ=1.5418),45kV,40mA;DS:1°,SS:1°,RS:1°;:0.02°,10°～90°,5°/min;Micro-meriticsASAP2020(N2,-196℃)BET、;S-4700;(PerkinElmerSpectrumOne).1.3　La2O3CeO21.2L,1.1L,[11].,La2O3CeO2(200mg/L)1mL(:100mg/L),,0.1mol/LNa2SO3(),0.45μm,,.Agilent4890(FID),:(HP-5,15m×0.53mm×1.5μm),:260℃,:300℃,:150℃,:20psi.1.;2.;3.;4.KI;5.;6.1　2　结果与讨论2.1　XRD2La2O3CeO2XRD.PDF,800℃La2O3,4%,96%;400℃CeO2100%.XRD(HFMW),ScherrerLa2O3100nm(Scherrer50nm,),CeO25～10nm.2　La2O3CeO2XRD2.2　、3La2O3CeO2N2--,3,La2O3,,(0.00399cm3/g,6.7nm),BET,2.39m2/g,;CeO2,(XRD),10nm,·78·　　　　　　　　　　　　　　　　　　　　　41　(0.101642cm3/g,10nm),BET40.71m2/g.3　La2O3CeO2-2.3　SEMLa2O3CeO2SEM4.4(a)4(b),400℃CeO2,CeO2,,4;4(c)4(d),800℃La2O3,,.2.4　5La2O3CeO2.5,La2O3CeO2,640cm-1、850cm-1、1060cm-1、1390cm-1、1492cm-1、1640cm-1、2918cm-1、3400cm-13610cm-1,La2O3,640cm-1O-La;16403400cm-1H-O-HOH,,;1492cm-1C-O-C;2918cm-1C-H.4　La2O3CeO2SEM5　La2O3CeO22.5　La2O3CeO26La2O3CeO2(pCNB).6,pCNB,2min13.5%,20min,37.2%,10min.La2O3,,20min82.1%,50%2min;La2O3,CeO2,,20min24.3%,5min.La2O3CeO2,pCNB,20min6.7%9.9%,BETCeO2La2O3.La2O3CeO2pCNB·79·4,:La2O3CeO2,La2O3,,,,.pCNB=100μg/L;=0.35mg/L;=200mg/L;pH=5.66　La2O3CeO23　结　论1)La(NO3)3·6H2OCe(NO3)3·6H2O,La2O3CeO2.CeO2,La2O3BET、,,,.2)La2O3CeO2pCNB,20min6.7%9.9%.3)La2O3,pCNB,20min82.1%,45;CeO2,pCNB,20min24.3%.参考文献:[1]BELTRANFJ,RIVASFJ,ESPIONSRM.Catalytic　　ozonationofoxalicacidinanaqueousTiO2slurryreactor[J].AppliedCatalysisB:Environmental,2002,39(3):221-231.[2]BELTRAFJ,RIVASFJ,MONTEROdeER.Irontypecatalystsfortheozonationofoxalicacidinwater[J].WaterResearch,2005,39(15):3553-3564.[3]ZHANGT,CHENWP,MAJ,etal.Minimizingbro-mateformationwithceriumdioxideduringozonationofbromide-containingwater[J].WaterResearch,2008,42(14):3651-3658.[4]YANGYX,MAJ,QINQD,etal.Degradationofni-trobenzenebynano-TiO2catalyzedozonation[J].Jour-nalofMolecularCatalysisA:Chemical,2007,267(1-2):41-48.[5]DONGYM,YANGHX,HEK,etal.β-MnO2nanowires:AnovelozonationcatalystforwatertreatmentappliedcatalysisB:Environmental,2009,85(3-4):155-161.[6]COOPERC,BURCHR.Aninvestigationofcatalyticozonationfortheoxidationofhalocarbonsindrinkingwa-terpreparation[J].WaterResearch,1999,33(18):3695-3700.[7]KWONJH,DAIM,HALLSMD,etal.Insituinfra-redcharacterizationduringatomiclayerdepositionoflanthanumoxide[J].JPhysicalChemistryC,2009,113(2):654-660.[8]BCRNALS,CALVIOJJ,LOPEZ-CARTESC,etal.NanostructuralevolutionofhighloadingRh/lanthanacatalyststhroughthereparationandreductionsteps[J].CatalysisToday,1999,52(1):29-43.[9]SHENJM,CHENZL,XUZZ,etal.Kineticsandmechanismofdegradationofp-chloronitrobenzeneinwaterbyozonation[J].JournalofHazardousMaterials,2008,152(3):1325-1331.[10],,,.[J].,2002,1(3):149-153.[11]BADERH,HOIGNEJ.Determinationofozoneinwa-terbytheindigomethod[J].WaterResearch,1981,15(4):449-456.(　刘　彤)·80·　　　　　　　　　　　　　　　　　　　　　41