Effect of high temperature pretreatment on the thermal resistance properties of Pd/CeO_2/Al_2O_3 close-coupled catalysts
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摘要
Fresh Pd/CeO_2/Al_2O_3 close coupled catalyst was prepared by the stepwise impregnation method and calcined at 550 °C for 3 h, which was then pretreated at 700, 800, and 900 °C for 3 h, respectively. Finally, these pretreated catalysts were aged at 1000 °C for 3 h to study their anti-aging properties. The catalytic activities of the catalysts were investigated detailedly, and the results showed that the catalyst pretreated at 800 °C before aging treatment possessed the best anti-aging performance for C_3H_8 oxidation. XRD and XPS results indicated that well-crystallized CeO_2 particles were formed during calcinations at 800 °C, which made CeO_2 an effective promoter. HRTEM revealed that Pd particles found on the edge of CeO_2 over the aged catalyst pretreated at 800 °C were relatively smaller than those over the catalysts without pretreatment. H_2-TPR and XPS results also implied that the interaction between well-crystallized CeO_2 and Pd suppressed the deactivation of PdO sites and further enhanced the catalytic performance.
Fresh Pd/CeO_2/Al_2O_3 close coupled catalyst was prepared by the stepwise impregnation method and calcined at 550 °C for 3 h, which was then pretreated at 700, 800, and 900 °C for 3 h, respectively. Finally, these pretreated catalysts were aged at 1000 °C for 3 h to study their anti-aging properties. The catalytic activities of the catalysts were investigated detailedly, and the results showed that the catalyst pretreated at 800 °C before aging treatment possessed the best anti-aging performance for C_3H_8 oxidation. XRD and XPS results indicated that well-crystallized CeO_2 particles were formed during calcinations at 800 °C, which made CeO_2 an effective promoter. HRTEM revealed that Pd particles found on the edge of CeO_2 over the aged catalyst pretreated at 800 °C were relatively smaller than those over the catalysts without pretreatment. H_2-TPR and XPS results also implied that the interaction between well-crystallized CeO_2 and Pd suppressed the deactivation of PdO sites and further enhanced the catalytic performance.
Fresh Pd/CeO_2/Al_2O_3 close coupled catalyst was prepared by the stepwise impregnation method and calcined at 550 °C for 3 h, which was then pretreated at 700, 800, and 900 °C for 3 h, respectively. Finally, these pretreated catalysts were aged at 1000 °C for 3 h to study their anti-aging properties. The catalytic activities of the catalysts were investigated detailedly, and the results showed that the catalyst pretreated at 800 °C before aging treatment possessed the best anti-aging performance for C_3H_8 oxidation. XRD and XPS results indicated that well-crystallized CeO_2 particles were formed during calcinations at 800 °C, which made CeO_2 an effective promoter. HRTEM revealed that Pd particles found on the edge of CeO_2 over the aged catalyst pretreated at 800 °C were relatively smaller than those over the catalysts without pretreatment. H_2-TPR and XPS results also implied that the interaction between well-crystallized CeO_2 and Pd suppressed the deactivation of PdO sites and further enhanced the catalytic performance.
引文
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[2]Ka?par J,Fornasiero P,Hickey N.Automotive catalytic converters:current status and some perspectives.Catal.Today,2003,77(4):419.
[3]Ka?par J,Fornasiero P,Graziani M.Use of Ce O2-based oxides in the three-way catalysis.Catal.Today,1999,50(2):285.
[4]Jia L W,Shen M Q,Wang J,Wang J M,Chu X,Gu W W.Durability of three-way and close-coupled catalysts for Euro IV regulation.J.Rare Earths,2008,26(6):827.
[5]He S N,Cui Y J,Yao Y L,Fang R M,Shi Z H,Gong M C,Chen Y Q.Effects of alkaline earth metal on performance of Zr O2-Al2O3 support and Pd-Rh close-coupled catalyst.Acta Phys-Chim.Sin.,2011,5(27):1157.
[6]Ozawa M,Nishio Y.Thermal stabilization ofγ-alumina with modification of lanthanum through homogeneous precipitation.J.Alloys Compd.,2004,374(1-2):397.
[7]Lan L,Chen S H,Cao Y,Zhao M,Gong M C,Chen Y Q.Preparation of ceria-zirconia by modified coprecipitation method and its supported Pd-only three-way catalyst.J.Colloid Inter.Sci.,2015,450:404.
[8]T?rncrona A,Skoglundh M,Thorm?hlen P,Fridell E,Jobson E.Low temperature catalytic activity of cobalt oxide and ceria promoted Pt and Pd:influence of pretreatment and gas composition.Appl.Catal.B:Environ.,1997,14(1-2):131.
[9]Hu W,Wang Y,Shang H Y,Xu H D,zhong L,Chen J J,Gong M C,Chen Y Q.Effects of Zr addition on the performance of the Pd-Pt/Al2O3 catalyst for lean-burn natural gas vehicle exhaust purification.Acta Phys-Chim.Sin.,2015,31:1171.
[10]Zhou R M,Xing F,Wang S Y,Lu J Q,Jin L Y,Luo M F.CO and C3H8 total oxidation over Pd/La-Al2O3 catalysts:Effect of calcination temperature and hydrothermal treatment.J.Rare Earths,2014,32(7):621.
[11]Hinokuma S,Fujii H,Okamoto M,Ikeue K,Machida M.Metallic Pd nanoparticles formed by Pd-O-Ce interaction:A reason for sintering-induced activation for CO oxidation.Chem.Mater.,2010,22(22):6183.
[12]Colussi S,Trovarelli A,Groppi G,Llorca J.The effect of Ce O2 on the dynamics of Pd-Pd O transformation over Pd/Al2O3 combustion catalysts.Catal.Commun.,2007,8(8):1263.
[13]Feio L S F,Hori C E,Damyanova S,Noronha F B,Cassinelli W H,Marques C M P,Bueno J M C.The effect of ceria content on the properties of Pd/Ce O2/Al2O3 catalysts for steam reforming of methane.Appl.Catal.A:General.,2007,316(1):107.
[14]Slavinskaya E M,Gulyaev R V,Zadesenets A V,Stonkus O A,Zaikovskii V I,Shubin Y V,Korenev S V,Boronin A I.Low-temperature CO oxidation by Pd/Ce O2 catalysts synthesized using the coprecipitation method.Appl.Catal.B:Environ.,2015,166-167:91.
[15]Liu S,Wu X D,Weng D,Ran R.Ceria-based catalysts for soot oxidation:a review.J.Rare Earths,2015,33(6):567.
[16]Gholami R,Smith K J.Activity of Pd O/Si O2 catalysts for CH4 oxidation following thermal treatments.Appl.Catal.B:Environ.,2015,168-169:156.
[17]Colussi S,Gayen A,Farnesi Camellone M,Boaro M,Llorca J,Fabris S,Trovarelli A.Nanofaceted Pd-O sites in Pd-Ce surface superstructures:Enhanced activity in catalytic combustion of methane.Angewandte Chemie,2009,121(45):8633.
[18]Hungria A,Fernandezgarcia M,Anderson J,Martinezarias A.The effect of Ni in Pd-Ni/(Ce,Zr)O/Al O catalysts used for stoichiometric CO and NO elimination.Part 2:Catalytic activity and in situ spectroscopic studies.J.Catal.,2005,235(2):262.
[19]Lin S Y,Yang L Y,Yang X,Zhou R X.Redox properties and metal-support interaction of Pd/Ce0.67Zr0.33O2-Al2O3catalyst for CO,HC and NOx elimination.Appl.Surf.Sci.,2014,305:642.
[20]Colussi S,Trovarelli A,Vesselli E,Baraldi A,Comelli G,Groppi G,Llorca J.Structure and morphology of Pd/Al2O3and Pd/Ce O2/Al2O3 combustion catalysts in Pd-Pd Otransformation hysteresis.Appl.Catal.A:General.,2010,390(1-2):1.
[21]Nakatsuji T,Kunishige M,Li J,Hashimoto M,Matsuzono Y.Effect of Ce O2 addition into Pd/Zr-Pr mixed oxide on three-way catalysis and thermal durability.Catal.Commun.,2013,35(0):88.
[22]Zhou R X,Zhao B,Yue B H.Effects of Ce O2-Zr O2 present in Pd/Al2O3 catalysts on the redox behavior of Pd Ox and their combustion activity.Appl.Surf.Sci.,2008,254(15):4701.
[23]Senftle T P,van Duin A C T,Janik M J.The role of site stability in methane activation on PdxCe1-xOδsurfaces.ACS Catal.,2015.
[24]Cargnello M,Jaén J J D,Garrido J C H,Bakhmutsky K,Montini T,Gámez J J C,Gorte R J,Fornasiero P.Exceptional activity for methane combustion over modular Pd@Ce O2 subunits on functionalized Al2O3.Science,2012,337(6095):713.
[25]Yang X,Yang L Y,Lin S Y,Zhou R X.Effects of the addition of small quantities of ceria on the catalytic behavior of Pd-only close-coupled catalysts during automobile exhaust elimination.Chin.J.Catal.,2014,35(8):1267.
[26]Piras A,Trovarelli A,Dolcetti G.Remarkable stabilization of transition alumina operated by ceria under reducing and redox conditions.Appl.Catal.B:Environ.,2000,28(2):L77.
[27]Martínez-Arias A,Fernández-García M,Salamanca L N,Valenzuela R X,Conesa J C,Soria J.Structural and Redox properties of ceria in alumina-supported ceria catalyst supports.J.Phys.Chem.B.,2000,104(17):4038.
[28]Hicks R,Rigano C,Pang B.Thermal stability of palladium on ceria-doped alumina.Catal.Lett.,1990,6(3-6):271.
[29]Shyu J Z,Weber W H,Gandhi H S.Surface characterization of alumina-supported ceria.J.Phys.Chem.,1988,92(17):4964.
[30]Craciun R,Daniell W,Kn?zinger H.The effect of Ce O2structure on the activity of supported Pd catalysts used for methane steam reforming.Appl.Catal.A:General,2002,230(1-2):153.
[31]Adijanto L,Bennett D A,Chen C,Yu A S,Cargnello M,Fornasiero P,Gorte R J,Vohs J M.Exceptional thermal stability of Pd@Ce O2 core-shell catalyst nanostructures grafted onto an oxide surface.Nano Lett.,2013,13(5):2252.
[32]Chen C,Cao J,Cargnello M,Fornasiero P,Gorte R J.Hightemperature calcination improves the catalytic properties of alumina-supported Pd@ceria prepared by self assembly.J.Catal.,2013,306:109.
[33]Zhang Z L,Fan Y Z,Xin Y,Li Q,Li R R,Anderson J A,Zhang Z L.Improvement of air/fuel ratio operating window and hydrothermal stability for Pd-only three-way catalysts through a Pd-Ce2Zr2O8 superstructure interaction.Environ.Sci.Technol.,2015,49(13):7989.
[34]Ray J C,You K S,Ahn J W,Ahn W S.Mesoporous alumina(I):Comparison of synthesis schemes using anionic,cationic,and non-ionic surfactants.Microporous Mesoporous Mater.,2007,100(1-3):183.
[35]Priolkar K R,Bera P,Sarode P R,Hegde M S,Emura S,Kumashiro R,Lalla N P.Formation of Ce1-xPdxO2-δsolid solution in combustion-synthesized Pd/Ce O2 catalyst:XRD,XPS,and EXAFS investigation.Chem.Mater.,2002,14(5):2120.
[36]Lan L,Chen S H,Zhao M,Gong M C,Chen Y Q.The effect of synthesis method on the properties and catalytic performance of Pd/Ce0.5Zr0.5O2-Al2O3 three-way catalyst.J.Mol.Catal.A:Chem.,2014,394:10.
[37]Zhang G J,Shen Z R,Liu M,Guo C H,Sun P C,Yuan ZY,Li B H,Ding D T,Chen T H.Synthesis and characterization of mesoporous ceria with hierarchical nanoarchitecture controlled by amino acids.J.Phys.Chem.B,2006,110(51):25782.
[38]Rodrigues L M T S,Silva R B,Rocha M G C,Bargiela P,Noronha F B,Brand?o S T.Partial oxidation of methane on Ni and Pd catalysts:Influence of active phase and Ce O2modification.Catal.Today,2012,197(1):137.
[2]Ka?par J,Fornasiero P,Hickey N.Automotive catalytic converters:current status and some perspectives.Catal.Today,2003,77(4):419.
[3]Ka?par J,Fornasiero P,Graziani M.Use of Ce O2-based oxides in the three-way catalysis.Catal.Today,1999,50(2):285.
[4]Jia L W,Shen M Q,Wang J,Wang J M,Chu X,Gu W W.Durability of three-way and close-coupled catalysts for Euro IV regulation.J.Rare Earths,2008,26(6):827.
[5]He S N,Cui Y J,Yao Y L,Fang R M,Shi Z H,Gong M C,Chen Y Q.Effects of alkaline earth metal on performance of Zr O2-Al2O3 support and Pd-Rh close-coupled catalyst.Acta Phys-Chim.Sin.,2011,5(27):1157.
[6]Ozawa M,Nishio Y.Thermal stabilization ofγ-alumina with modification of lanthanum through homogeneous precipitation.J.Alloys Compd.,2004,374(1-2):397.
[7]Lan L,Chen S H,Cao Y,Zhao M,Gong M C,Chen Y Q.Preparation of ceria-zirconia by modified coprecipitation method and its supported Pd-only three-way catalyst.J.Colloid Inter.Sci.,2015,450:404.
[8]T?rncrona A,Skoglundh M,Thorm?hlen P,Fridell E,Jobson E.Low temperature catalytic activity of cobalt oxide and ceria promoted Pt and Pd:influence of pretreatment and gas composition.Appl.Catal.B:Environ.,1997,14(1-2):131.
[9]Hu W,Wang Y,Shang H Y,Xu H D,zhong L,Chen J J,Gong M C,Chen Y Q.Effects of Zr addition on the performance of the Pd-Pt/Al2O3 catalyst for lean-burn natural gas vehicle exhaust purification.Acta Phys-Chim.Sin.,2015,31:1171.
[10]Zhou R M,Xing F,Wang S Y,Lu J Q,Jin L Y,Luo M F.CO and C3H8 total oxidation over Pd/La-Al2O3 catalysts:Effect of calcination temperature and hydrothermal treatment.J.Rare Earths,2014,32(7):621.
[11]Hinokuma S,Fujii H,Okamoto M,Ikeue K,Machida M.Metallic Pd nanoparticles formed by Pd-O-Ce interaction:A reason for sintering-induced activation for CO oxidation.Chem.Mater.,2010,22(22):6183.
[12]Colussi S,Trovarelli A,Groppi G,Llorca J.The effect of Ce O2 on the dynamics of Pd-Pd O transformation over Pd/Al2O3 combustion catalysts.Catal.Commun.,2007,8(8):1263.
[13]Feio L S F,Hori C E,Damyanova S,Noronha F B,Cassinelli W H,Marques C M P,Bueno J M C.The effect of ceria content on the properties of Pd/Ce O2/Al2O3 catalysts for steam reforming of methane.Appl.Catal.A:General.,2007,316(1):107.
[14]Slavinskaya E M,Gulyaev R V,Zadesenets A V,Stonkus O A,Zaikovskii V I,Shubin Y V,Korenev S V,Boronin A I.Low-temperature CO oxidation by Pd/Ce O2 catalysts synthesized using the coprecipitation method.Appl.Catal.B:Environ.,2015,166-167:91.
[15]Liu S,Wu X D,Weng D,Ran R.Ceria-based catalysts for soot oxidation:a review.J.Rare Earths,2015,33(6):567.
[16]Gholami R,Smith K J.Activity of Pd O/Si O2 catalysts for CH4 oxidation following thermal treatments.Appl.Catal.B:Environ.,2015,168-169:156.
[17]Colussi S,Gayen A,Farnesi Camellone M,Boaro M,Llorca J,Fabris S,Trovarelli A.Nanofaceted Pd-O sites in Pd-Ce surface superstructures:Enhanced activity in catalytic combustion of methane.Angewandte Chemie,2009,121(45):8633.
[18]Hungria A,Fernandezgarcia M,Anderson J,Martinezarias A.The effect of Ni in Pd-Ni/(Ce,Zr)O/Al O catalysts used for stoichiometric CO and NO elimination.Part 2:Catalytic activity and in situ spectroscopic studies.J.Catal.,2005,235(2):262.
[19]Lin S Y,Yang L Y,Yang X,Zhou R X.Redox properties and metal-support interaction of Pd/Ce0.67Zr0.33O2-Al2O3catalyst for CO,HC and NOx elimination.Appl.Surf.Sci.,2014,305:642.
[20]Colussi S,Trovarelli A,Vesselli E,Baraldi A,Comelli G,Groppi G,Llorca J.Structure and morphology of Pd/Al2O3and Pd/Ce O2/Al2O3 combustion catalysts in Pd-Pd Otransformation hysteresis.Appl.Catal.A:General.,2010,390(1-2):1.
[21]Nakatsuji T,Kunishige M,Li J,Hashimoto M,Matsuzono Y.Effect of Ce O2 addition into Pd/Zr-Pr mixed oxide on three-way catalysis and thermal durability.Catal.Commun.,2013,35(0):88.
[22]Zhou R X,Zhao B,Yue B H.Effects of Ce O2-Zr O2 present in Pd/Al2O3 catalysts on the redox behavior of Pd Ox and their combustion activity.Appl.Surf.Sci.,2008,254(15):4701.
[23]Senftle T P,van Duin A C T,Janik M J.The role of site stability in methane activation on PdxCe1-xOδsurfaces.ACS Catal.,2015.
[24]Cargnello M,Jaén J J D,Garrido J C H,Bakhmutsky K,Montini T,Gámez J J C,Gorte R J,Fornasiero P.Exceptional activity for methane combustion over modular Pd@Ce O2 subunits on functionalized Al2O3.Science,2012,337(6095):713.
[25]Yang X,Yang L Y,Lin S Y,Zhou R X.Effects of the addition of small quantities of ceria on the catalytic behavior of Pd-only close-coupled catalysts during automobile exhaust elimination.Chin.J.Catal.,2014,35(8):1267.
[26]Piras A,Trovarelli A,Dolcetti G.Remarkable stabilization of transition alumina operated by ceria under reducing and redox conditions.Appl.Catal.B:Environ.,2000,28(2):L77.
[27]Martínez-Arias A,Fernández-García M,Salamanca L N,Valenzuela R X,Conesa J C,Soria J.Structural and Redox properties of ceria in alumina-supported ceria catalyst supports.J.Phys.Chem.B.,2000,104(17):4038.
[28]Hicks R,Rigano C,Pang B.Thermal stability of palladium on ceria-doped alumina.Catal.Lett.,1990,6(3-6):271.
[29]Shyu J Z,Weber W H,Gandhi H S.Surface characterization of alumina-supported ceria.J.Phys.Chem.,1988,92(17):4964.
[30]Craciun R,Daniell W,Kn?zinger H.The effect of Ce O2structure on the activity of supported Pd catalysts used for methane steam reforming.Appl.Catal.A:General,2002,230(1-2):153.
[31]Adijanto L,Bennett D A,Chen C,Yu A S,Cargnello M,Fornasiero P,Gorte R J,Vohs J M.Exceptional thermal stability of Pd@Ce O2 core-shell catalyst nanostructures grafted onto an oxide surface.Nano Lett.,2013,13(5):2252.
[32]Chen C,Cao J,Cargnello M,Fornasiero P,Gorte R J.Hightemperature calcination improves the catalytic properties of alumina-supported Pd@ceria prepared by self assembly.J.Catal.,2013,306:109.
[33]Zhang Z L,Fan Y Z,Xin Y,Li Q,Li R R,Anderson J A,Zhang Z L.Improvement of air/fuel ratio operating window and hydrothermal stability for Pd-only three-way catalysts through a Pd-Ce2Zr2O8 superstructure interaction.Environ.Sci.Technol.,2015,49(13):7989.
[34]Ray J C,You K S,Ahn J W,Ahn W S.Mesoporous alumina(I):Comparison of synthesis schemes using anionic,cationic,and non-ionic surfactants.Microporous Mesoporous Mater.,2007,100(1-3):183.
[35]Priolkar K R,Bera P,Sarode P R,Hegde M S,Emura S,Kumashiro R,Lalla N P.Formation of Ce1-xPdxO2-δsolid solution in combustion-synthesized Pd/Ce O2 catalyst:XRD,XPS,and EXAFS investigation.Chem.Mater.,2002,14(5):2120.
[36]Lan L,Chen S H,Zhao M,Gong M C,Chen Y Q.The effect of synthesis method on the properties and catalytic performance of Pd/Ce0.5Zr0.5O2-Al2O3 three-way catalyst.J.Mol.Catal.A:Chem.,2014,394:10.
[37]Zhang G J,Shen Z R,Liu M,Guo C H,Sun P C,Yuan ZY,Li B H,Ding D T,Chen T H.Synthesis and characterization of mesoporous ceria with hierarchical nanoarchitecture controlled by amino acids.J.Phys.Chem.B,2006,110(51):25782.
[38]Rodrigues L M T S,Silva R B,Rocha M G C,Bargiela P,Noronha F B,Brand?o S T.Partial oxidation of methane on Ni and Pd catalysts:Influence of active phase and Ce O2modification.Catal.Today,2012,197(1):137.