采用XRF、XRD、SEM和CH4-TPR表征手段,研究了Ce改性ZSM-5分子筛载Pd催化剂在CO、CH4氧化过程中的CeO2-Pd协同作用。结果表明,经Ce改性后ZSM-5分子筛的载Pd量提高;Pd/Ce-ZSM-5催化剂对 CH4的起始吸附温度降低;Pd/Ce-ZSM-5催化剂中 Ce 主要以 CeO2形态存在。Pd是CO的催化氧化活性物种,CeO2-Pd协同作用可促进CO的氧化。Pd和PdO均是CH4的催化氧化活性物种,CeO2的供氧-储氧特性有助于Pd→PdO的转化,CeO2与Pd的相互作用使Pd/Ce-ZSM-5催化剂具有高的CO和CH4催化氧化活性。
CeO2-Pd interactions in Ce-modified ZSM-5 supported Pd catalyst for oxidation of CO and CH4 is investigated by XRF, XRD, SEM and CH4-TPR. The results show that amount of supported Pd in Ce-ZSM-5 is increased. For Pd/Ce-ZSM-5, adsorption starting-temperature of CH4 is decreased. Cerium oxide (CeO2) is mainly in Pd/Ce-ZSM-5 catalyst. Activated species of CO oxidation is Pd. Conversion rate of CO oxidation is increased because of CeO2-Pd interaction. Activated species of CH4 oxidation are Pd and PdO. Transformation of Pd→PdO is promoted by supply-storage oxygen of CeO2. Activity of Pd/Ce-ZSM-5 for CO and CH4 oxidation is enhanced due to interaction between CeO2 and Pd.
参考文献
[1] | 胡宏杰,赵恒勤,王立卓.沸石分子筛的制备及应用[J].矿产保护与利用,1998(05):10-13. |
[2] | 王绪绪,陈旬,徐海兵,付贤智.沸石分子筛的表面改性技术进展[J].无机化学学报,2002(06):541-549. |
[3] | 季东,苏怡,刘涛,汪毅,张忠东,张海涛,高雄厚.ZSM-5沸石分子筛增产丙烯表面改性的研究进展[J].分子催化,2007(04):371-377. |
[4] | Jordan K. Lampert;M. Shahjahan Kazi;Robert J. Farrauto .Palladium catalyst performance for methane emissions abatement from lean burn natural gas vehicles[J].Applied Catalysis, B. Environmental: An International Journal Devoted to Catalytic Science and Its Applications,1997(3/4):211-223. |
[5] | Deborah L. Mowery;Michael S. Graboski;Robert L. McCormick;Tim R. Ohno .Deactivation of PdO-Al_2O_3 oxidation catalyst in lean-burn natural gas engine exhaust: aged catalyst characterization and studies of poisoning by H_2O and SO_2[J].Applied Catalysis, B. Environmental: An International Journal Devoted to Catalytic Science and Its Applications,1999(3):157-169. |
[6] | Patrick Gelin;Michel Primet .Complete oxidation of methane at low temperature over noble metal based catalysts: a review[J].Applied Catalysis, B. Environmental: An International Journal Devoted to Catalytic Science and Its Applications,2002(1):1-37. |
[7] | Mowery D L;McCormick R L .Deactivation of alumina supported and unsupported PdO methane oxidation catalyst:the effect of water on sulfate poisoning[J].Applied Catalysis B:Environmental,2001,34(04):287-297. |
[8] | Li Y;Armor J N .Catalytic combustion of methane over palladium exchanged zeolites[J].Applied Catalysis B:Environmental,1994,3(04):275-282. |
[9] | 毕玉水,吕功煊.铈改性NaZSM-5分子筛担载Pd催化剂上CO氧化性能研究[J].化学学报,2003(04):635-640. |
[10] | Yushui Bi;Gongxuan Lu .Catalytic CO oxidation over palladium supported NaZSM-5 catalysts[J].Applied Catalysis, B. Environmental: An International Journal Devoted to Catalytic Science and Its Applications,2003(3):279-286. |
[11] | 王辉,张汉军,孔德金,陈庆龄,高滋.ZSM-5催化剂水蒸汽处理对甲苯选择性歧化性能的影响[J].石油化工,2000(06):400-403. |
[12] | 葛晓萍;牛淑妍;王世权 .水热处理前后不同改性ZSM-5催化剂性能的研究[J].齐鲁石油化工,1997,25(01):22-27. |
[13] | R.Burch;D.J.Crittle;B.W.L.Southward;J.A.Sullivan .The effect of SO_2 on the activity of Pd-based catalysts in methane combustion[J].Catalysis Letters,2001(3/4):153-155. |
[14] | Gélin P;Urfels L;Primet M et al.Complete oxidation of methane at low temperature over Pt and Pd catalysts for the abatement of lean-burn natural gas fuelled vehicles emissions:influence of water and sulphur containing compounds[J].Catalysis Today,2003,83(01):45-57. |
[15] | Jones J M;Dupont V A;Brydson R et al.Sulphur poisoning and regeneration of precious metal catalysed methane combustion[J].Catalysis Today,2003,81(04):589-601. |
[16] | 杨少华,崔英德,陈循军,涂星.ZSM-5沸石分子筛的合成和表面改性研究进展[J].精细石油化工进展,2003(04):47-50. |
[17] | Fukui K.;Namai Y.;Iwasawa Y. .Imaging of surface oxygen atoms and their defect structures on CeO2(111) by noncontact atomic force microscopy[J].Applied Surface Science: A Journal Devoted to the Properties of Interfaces in Relation to the Synthesis and Behaviour of Materials,2002(3/4):252-256. |
[18] | 蔺广森,戴红,常仕英,赵云昆,王亚明,杨冬霞.Ce元素改性对分子筛性能的影响[J].贵金属,2013(02):30-34. |
[19] | 戴红,宁远涛.Pd的氧化与表面状态[J].稀有金属材料与工程,2011(07):1256-1259. |
[20] | Oh S H;Eickel C C .Effects of cerium addition on CO oxidation kinetics over alumina-supported rhodium catalysts[J].Journal of Catalysis,1988,112(02):543-555. |
[21] | 李梅 .铈基稀土化合物的物性控制及应用研究[D].北京化工大学,2008. |
[22] | 赫崇衡,朱明,金国林,徐佩若,汪仁.氧化铈对Pd催化剂氧化活性和热稳定性的影响[J].应用化学,2004(02):154-158. |
[23] | 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. |
[24] | F.Arosio;S.Colussi;A.Trovarelli .Effect of alternate CH4-reducing/lean combustion treatments on the reactivity of fresh and S-poisoned Pd/CeO2/Al2O3 catalysts[J].Applied Catalysis, B. Environmental: An International Journal Devoted to Catalytic Science and Its Applications,2008(3/4):335-342. |
[25] | F.Arosio;S.Colussi;G.Groppi .Regeneration of S-poisoned Pd/Al_2O_3 catalysts for the combustion of methane[J].Catalysis Today,2006(4):569-576. |
[26] | Sara Colussi;Carla de Leitenburg;Giuliano Dolcetti .The role of rare earth oxides as promoters and stabilizers in combustion catalysts[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,2004(1/2):387-392. |
[27] | Slavinskaya, EM;Boronin, AI;Danilova, IG;Amosov, YI;Ivanova, AS;Kuznetsov, PA;Polukhina, IA;Gulyaev, RV;Stadnichenko, AI;Koshcheev, SV;Zaikovskii, VI;Noskov, AS .Synthesis and Physicochemical Characterization of Palladium-Cerium Oxide Catalysts for the Low-Temperature Oxidation of Carbon Monoxide[J].Kinetics and catalysis,2009(6):819-823. |
[28] | Shyu J Z;Otto K;Watkins W L H et al.Characterization of Pd/γ-alumina catalysts containing ceria[J].Journal of Catalysis,1988,114(01):23-33. |
[29] | Groppi G;Cristiani C;Lietti L et al.Effect of ceria on palladium supported catalysts for high temperature combustion of CH4 under lean conditions[J].Catalysis Today,1999,50(02):399-412. |
[30] | Zafiris G S;Gorte R J .Evidence for low-temperature oxygen migration from ceria to Rh[J].Journal of Catalysis,1993,139(02):561-567. |
[31] | Nibbelke RH.;Hoebink JHBJ.;Marin GB.;Campman MAJ. .KINETIC STUDY OF THE CO OXIDATION OVER PT/GAMMA-AL2O3 AND PT/RH/CEO2/GAMMA-AL2O3 IN THE PRESENCE OF H2O AND CO2[J].Journal of Catalysis,1997(2):358-373. |
[32] | Nibbelke R H;Nievergeld A J L;Hoebink J H B J et al.Development of a transient kinetic model for the CO oxidation by O2 over a Pt/Rh/CeO2/γ-Al2O3 three-way catalyst[J].Applied Catalysis B:Environmental,1998,19(03):245-259. |
[33] | R.Rajasree;J.H.B.J.Hoebink;J.C.Schouten .Transient kinetics of carbon monoxide oxidation by oxygen over supported palladium/ceria/zirconia three-way catalysts in the absence and presence of water and carbon dioxide[J].Journal of Catalysis,2004(1):36-43. |
[34] | Huaqing Zhu;Zhangfeng qin;Wenjuan Shan;WenjieShen;Jianguo Wang .Pd/CeO2-TiO2 catalyst for CO oxidation at low temperature:a TPR study with H2 and CO as reducing agents[J].Journal of Catalysis,2004(2):267-277. |
[35] | Zafiris G S;Gorte R J .Evidence for a second CO oxidation mechanism on Rh/ceria[J].Journal of Catalysis,1993,143(01):86-91. |
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