【摘要】 本文采用溶胶 -凝胶法制备了负载在γ- Al2 O3上 ,含有 Ce- Zr、Pr- Zr、Ce- Pr- Zr固溶体的样品。进行了三效催化活性的评价 ,程序升温还原 ( TPR)表征和储氧量的测定。结果表明 ,样品均具有较高的三效催化活性 ,尤其是含有 Pr的样品 ,老化后在富氧区 ( S=1 .30 )的 NOx 转化率较高 ,达到 65%以上 ,其中由 Pr修饰的 Ce- Zr固溶体的样品的储氧量最大。更多还原

【Abstract】 A sol gel route was proceeded to prepare the catalytic procursors Ce Zr,Pr Zr and Ce Pr Zr mixed oxides,supported on a γ alumina.The three way catalysts containing low precious metals were prepared with impregnation method.The measurements of the oxygen storage capacity (OSC) and temperature programmed reduction (TPR) were used to characterize the properties of the catalysts.The three way catalytic actvities of these samples were also evaluated.It is shown that the catalyst containing Ce Zr modified by Pr possesses the largest oxygen storage capacity.The catalyat containing Pr maintains a higher NO x conversion up to 65% than that of the sample containing the original Ce Zr solid solution at the lean region (S=1 30) after aged at 850℃.更多还原