Acta Chimica Sinica ›› 2001, Vol. 59 ›› Issue (5): 713-717. Previous Articles     Next Articles

Original Articles

铜锆复合氧化物的结构对其催化选 择还原-氧化氮性 能的影响

马军;尉继英;朱月香;冯华升;蔡小海;谢有畅   

  1. 北京大学物理化学研究所.北京(100871)
  • 出版日期:2001-05-15 发布日期:2001-05-15

The structure of CuO---ZrO~2mixed oxides and its infiuence on the catalytic selective reduction of NO by propene

Ma Jun;Wei Jiying;Zhu Yuexiang;Feng Huasheng;Cai Xiaohai;Xie Youchang   

  1. Beijing Univ, Inst Phys Chem.Beijing(100871)
  • Online:2001-05-15 Published:2001-05-15

Different catalytic performances of CuO---ZrO~2 mixed oxides prepared by impregnation or co-precipitiation method for selective reduction of NO( in the presence of O~2) were invstigated. The sturctures and properties of the catalysts were characterized by XRD, BET surface area measurement, EXAFS and H~2 ---TPR measurements. The CuO---ZrO~2 mixed oxides prepared by impregnation method had larger surface area than those prepared by c0- precipitation methos. The zirconium oxide was stabilized at the tetragonal phase. EXAFS measurement shows that in the CuO--- ZrO~2 mixed oxides prepared by impregnation method the copper ions first fill in the syrface hole of zirconium oxide and stay there as cu^+. Under the calcination at 500℃ , the Cu^2+ ions that brought into ZeO~2 by co-precipitation method can replace Zr^4+ and form a uniform amorphous solid solution. The high -dispersion of Cu ions in zirconium oxide was the element that led to formation of highly dispersed isolated copper species on the surface. Substitution of Zr^ 4+ by Cu^2+ ions aould decrease the reducibility of copper species and the activity of the complete oxidation of propene. The local structure difference of copper species was the main reason for the high activity and selectivity of the CuO---ZrO~2 mixed oxides prepared by c0-precipitation method.

Key words: COPPER OXIDE, ZIRCONIUM OXIDE, NITROGEN MONOXIDE, CATALYTIC BEHAVIOUR, X-RAY DIFFRACTION ANALYSIS, TEMPERATURE PROGRAMMED REDUCTION

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