CO Oxidation over Mono and Bi-Metallic Sequentially Impregnated Pd-Pt Catalysts

被引:0
作者
Kaya, Sarp [1 ,2 ]
Uner, Deniz [1 ]
机构
[1] Middle E Tech Univ, Dept Chem Engn, TR-06531 Ankara, Turkey
[2] Stanford Linear Accelerator Ctr, Menlo Pk, CA 94025 USA
关键词
CO oxidation; bimetallic catalysts; palladium; platinum;
D O I
暂无
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
The CO oxidation capability of sequentially impregnated Pd-Pt/gamma-Al2O3 bimetallic catalysts was tested. The CO oxidation light-off curves were hierarchically spaced between monometallic Pd and monometallic Pt, which showed the highest and lowest activity, respectively, indicating that sequential impregnation did not result in the formation of bimetallic particles, but that the catalysts remained as monometallic entities over the support surface. An investigation of the effect of CO partial pressure on the reaction rates over monometallic catalysts indicated that in the presence of excess CO the surface of Pt was poisoned. On the other hand, in the presence of excess CO the reaction rates over Pd catalysts remained constant due to the availability of the subsurface oxygen pools in PdO layers.
引用
收藏
页码:645 / 652
页数:8
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