以θ-Al2O3为载体,采用浸渍法制备了PdO/θ-Al2O3和PdO/CeO2/θ-Al2O3催化剂,比较了催化剂的CO氧化活性和热稳定性.运用X射线粉末衍射(XRD),程序升温还原(H2-TPR),拉曼光谱(Raman),CO化学吸附和物理吸附(BET)等技术对催化剂进行了表征.结果表明,PdO/θ-Al2O3催化剂经过1000℃焙烧后CO氧化活性较低;而PdO/CeO2/θ-Al2O3催化剂经过1000 ℃焙烧后CO氧化活性反而高于500℃焙烧的活性.CeO2能有效提高PdO/CeO2/θ-Al2O3催化剂的热稳定性,在10 h的稳定性实验中无失活现象发生.PdO/CeO2/θ-Al2O3-1000催化剂具有最高的转换频率(TOF =3.36 s-1).
参考文献
[1] | Schryer D R;Upchurch B T;Sidney B D;Brown K G Hoflund G B Herz R K .A proposed mechanism for Pt/SnOx-catalyzed CO oxidation[J].Journal of Catalysis,1991,130:314. |
[2] | Tripathi A K;Gupta N M;Chatterjee U K;Bhawalkar D D .Development of a sealed-off cw CO2 laser using a supported gold catalyst[J].Review of Scientific Instruments,1994,65:3853. |
[3] | Funazaki N;Hemmi A;Ito S;Asano Y,Yamashita S,Kobayashi T,Haruta M .Development of carbon monoxide detector using Au fine particles-doped α-Fe2O3[J].Sensors and Actuators B:Chemical,1993,14:536. |
[4] | Andrew A. Herzing;Christopher J. Kiely;Albert F. Carley;Philip Landon;Graham J. Hutchings .Identification of Active Gold Nanoclusters on Iron Oxide Supports for CO Oxidation[J].Science,2008(5894):1331-1335. |
[5] | Zhu HQ;Qin ZF;Shan WJ;Shen WJ;Wang JG .Low-temperature oxidation of CO over Pd/CeO2-TiO2 catalysts with different pretreatments[J].Journal of Catalysis,2005(1):41-50. |
[6] | Wu Z L;Li M J;Overbury S H .On the structure dependence of CO oxidation over CeO2 nanocrystals with well-defined surface planes[J].Journal of Catalysis,2012,285:61. |
[7] | Jia, A.-P.;Hu, G.-S.;Meng, L.;Xie, Y.-L.;Lu, J.-Q.;Luo, M.-F..CO oxidation over CuO/Ce _(1-x)Cu _xO _(2-δ) and Ce _(1-x)Cu _xO _(2-δ) catalysts: Synergetic effects and kinetic study[J].Journal of Catalysis,2012:199-209. |
[8] | Luo M F;Zhong Y J;Yuan X X;Zheng X M .TPR and TPD studies of CuO/CeO2 catalysts for low temperature CO oxidation[J].Applied Catalysis A:General,1997,162:121. |
[9] | 吴肖霞,余强,姚小江,董林.CuOx/CeO2催化剂物种演变及其对CO富氢氧化反应的影响[J].中国稀土学报,2013(02):181-189. |
[10] | Liu Z L;Fu Y L;Tu J;Meng M .Effect of CeO2 on supported Pd catalyst in the SCR of NO:A DRIFT study[J].Catalysis Letters,2002,81:285. |
[11] | Li, JY;Ma, L;Li, XN;Lu, CS;Liu, HZ .Effect of nitric acid, pretreatment on the properties of activated carbon and supported palladium catalysts[J].Industrial & Engineering Chemistry Research,2005(15):5478-5482. |
[12] | Wang S Y;Li N;Zhou R M;Jin L Y Hu G S Lu J Q Luo M F .Comparing the CO oxidation activity of free PdO and Pd2+ ions over PdO-CeO2/SiO2 catalysts[J].Journal of Molecular Catalysis A:Chemical,2013,374-375:53. |
[13] | Deshpande S;Patil S;Kuchibhatla SVNT;Seal S .Size dependency variation in lattice parameter and valency states in nanocrystalline cerium oxide[J].Applied physics letters,2005(13):3113-1-3113-3-0. |
[14] | Meng L;Lin J J;Pu Z Y;Luo L F Jia A P Huang W X Luo M F Lu J Q .Identification of active sites for CO and CH4 oxidation over PdO/Ce1-xPdxO2-δ catalysts[J].Applied Catalysis B:Environmental,2012,119-120:117. |
[15] | 肖小燕,鲁继青,苏孝文,郭明,罗孟飞.PdO-CeO2复合氧化物催化剂的CO低温氧化[J].物理化学学报,2009(03):561-566. |
[16] | McCaulley J A .In-situ X-ray absorption spectroscopy studies of hydride and carbide formation in supported palladium catalysts[J].Journal of Physical Chemistry,1993,97:10372. |
[17] | Priolkar KR.;Bera P.;Sarode PR.;Hegde MS.;Emura S.;Kumashiro R. Lalla NP. .Formation of Ce1-xPdxO2-delta solid solution in combustion-synthesized Pd/CeO2 catalyst: XRD, XPS, and EXAFS investigation[J].Chemistry of Materials,2002(5):2120-2128. |
[18] | Bera P;Patil K C;Jayaram V;Subbanna G N Hegde M S .Ionic dispersion of Pt and Pd on CeO2 by combustion method:effect of metal-ceria interaction on catalytic activities for NO reduction and CO and hydrocarbon oxidation[J].Journal of Catalysis,2000,196:293. |
[19] | Kurnatowska M;Kepinski L;Mista W .Structure evolution of nanocrystalline Ce1-z PdxO2-y mixed oxide in oxidizing and reducing atmosphere:Reduction-induced activity in low-temperature CO oxidation[J].Applied Catalysis B:Environmental,2012,117-118:135. |
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