铂钯双金属纳米催化剂的催化活性

251()Vol.25No.120063JournalofSouth-CentralUniversityforNationalities(Nat.Sci.Edition)Mar.2006a王　然　何宝林*　[马来]刘光荣　盘荣俊(,430074),,,Pt-Pd,,,pH,.;;;pHTB383A1672-4321(2006)01-0001-04InvestigationofCatalyticActivityofPt/PdNanobimetallicCatalystWangRanHeBaolin[Malaysia]LiewKongrongPanRongjunAbstractPolymerstabilizedplatinumnano-sizecatalysthasrelativelyhighhydrogenationactivity.Introductionofasecondmetal,palladium,toformacoreshellstructurewithPdastheshellandPtasthecore,enhancesthecatalyticactivitysubstantially.TheenhancementvarieswiththeamountofPdintroduced.ChangesinpHwasalsofoundtohavesignificanteffectsonthecatalyticactivity.KeywordsPd/Ptbimetalcatalyst;cyclohexene;catalytichydrogenation;pHWangRanMastersCandidate,KeylaboratoryforCatalysisandMaterialScienceofHubeiProvince,CollegeofChemistryandMaterialScience,SCUFN,Wuhan430074,China[14],.,22,,,[5,6],,[7].,PVPPtPdPt-Pd,pH.11.11.1.1,,PVP(K30)[8].:250mL,0.555g(5mmol)PVP0.065g0.125mmolH2PtCl6H2O65mL75mLH2O,180minPt,10mL0.1mol/L.1.1.2Pt/Pd,PtPd,PVP-Pt0.5sPd0.5(0.5Pt1.1.1Pt0.5,0.625mmol,nPt/nPd=1/1),:75mLPVP-Pt0.287gPVP(2.5mmol)6.5mL9.6mmol/LH2PdCl4nH2O32.5mL31.0mL,180a2005-10-31*[e-mail](1980-),,,:,E-mail:[e-mail](MZY02019)min,5mL0.1mol/L.PVP-Pt0.5sPd0.25(nPt/nPd=2/1)PVP-Pt0.5sPd0.75(nPt/nPd=2/3):PVP-Pt0.5sPd0.253.25mL9.6mmol/LH2PdCl4nH2O,0.031mmolPd;Pt0.5sPd0.759.75mL9.6mmol/LH2PdCl4nH2O,0.094mmolPd.1.1.3(TEM),.TEMFEITacnacG220S-Twin,200kV.300,.1.2,.:0.5mol/LNaHSO3,NaHSO3,2,,;,NaHSO3,,3,,,,CaCl2,N2,.1.330mL,4.0mL,8.0mL,N2,H2N2,30,H20.1MPa30,1h,2.0mL0.5mol/L,,,GC(HP-5:12m0.22mm).HClpH,pH.22.1TEMPVP-PtTEM1.(a)PVP-Pt;(b)PVP-Pt0.5sPd0.25;(c)PVP-Pt0.5sPd0.5;(d)PVP-Pt0.5sPd0.751()()Fig1TEMmicrographs(left)andparticlesizedistributionhistograms(right)2()251PVP-Pt,,,.,,PdPt,.Pd,.2.2.300.1MPa,PVP,.2.,,.1.1PVP-Pt,pH,pH=6.5,3mLH2(min-1m-2),77min,HClpH,pH=5.54.53.5,4,111012,,202815min,100%,pH=3.5.pH,,PVP-Pt0.5sPd0.25,pH=6.523.,pH=6.5,,PVP-Pt,,PVP-Pt0.5sPd0.514mLH2min-1m-2,PVP-Pt0.5sPd0.75PVP-Pt0.5sPd0.25.PdPt[4],Pd.PVP-Pt0.5sPd0.75,,Pt0.5sPd0.75,PtPd,Pd.(a)Pt;(b)Pt0.5sPd0.25;(c)Pt0.5sPd0.5;(d)Pt0.5sPd0.7521.010-3mol,3.310-3mmol,0.1MPa.303KFig2Hydrogenationofcyclohexenewithdifferentcatalystswithcyclohexene1.010-3molandcatalyst,3.310-3mmolat0.1MPaand303K31,:11)Tab1HydrogenationofcyclohexenebyPVP-PtandPVP-Pt0.5sPdypH2)t/minH2/(mLmin-1m-2)3)/%PVP-Pt6.57731005.520111004.528101003.51512100PVP-Pt0.5sPd0.256.5489945.51125924.512251003.5931100PVP-Pt0.5sPd0.56.51814915.5823974.511211003.51220100PVP-Pt0.5sPd0.756.530101005.5921994.518171003.51516100*1)PdPt,y0.250.50.75;2);3).,PVP-PtPd,,pH,pH.[1]YuW,WangY,LiuH,etal.Preparationandcharac-terizationofpolymer-protectedPt/Cobimetalliccol-loidsandtheircatalyticpropertiesintheselectivehy-drogenationofcinnamaldehyde[J].MolCatalA:Chem,1996,112:105.[2]LiuM,YuW,LiuH,etal.Preparationandcharac-terizationofpolymer-stabilizedruthenium-platinumandruthenium-palladiumBimetalliccolloidsandtheircatalyticpropertiesforhydrogenationofo-chloroni-trobenzene[J].ColloidInterfaceSci,1999,214:231-237.[3]ChooHP,LiewKY,LiuHF,etal.Activityandse-lectivityofnoblemetalcolloidsforthehydrogenationofpolyunsaturatedsoybeanoil[J].MolCataA:Chem,2003,191:113-121.[4]ChooHP,LiewKY,LiuHF,etal.Hydrogena-tionofpalmoleincatalyzedbypolymerstabilizedPtcolloids[J].MolCatalA:Chem,2001,165:127-134.[5]MisumiY,IshiiY,HidaiM.Homogeneousmulti-metalliccatalysts:part10formylationofarylandalkenyliodidesbypalladium-rutheniumbimetalliccatalysts[J].MolCatal,1993,78:1.[6]TosimaN,HaradaM,YonezawaT,etal.Structuralanalysisofpolymer-protectedpalladium/platinumbimetallicclustersasdispersedcatalystsbyusingex-tendedx-rayabsorptionfinestructurespectroscopy[J].PhysChem,1991,95:7448.[7]BronsteinLM,ChernyshovDM,VolkovIO,etal.Structureandpropertiesofbimetalliccolloidsformedinpolystyrene-block-Poly-4-vinylpyridinemi-celles:catalyticbehaviorinselectivehydrogenationofdehydrolinalool[J].Cata,2000,196:302-314.[8]LiuM.Instituteofchemistry(PhDThesis)[D].Bei-jing:ChineseAcademyofScience,1999.4()25