Pt/Mg-Al-O催化剂上NO_x的存储性能  

NO_x Storage Performance of Pt/Mg-Al-O Catalyst

作　　者：程昊[1] 陈光文[1] 王树东[1] 吴迪镛[1] 张引[1] 李恒强[1] 

机构地区：[1]中国科学院大连化学物理研究所,辽宁大连116023

出　　处：《催化学报》2004年第4期272-276,共5页

基　　金：国家 8 63高技术项目 ( 2 0 0 1AA64 3 0 40 )

摘　　要：采用共沉淀 浸渍法制备了不同Mg/Al比的Pt/Mg Al O催化剂 ,并用XRD和TPD等方法进行了表征 .考察了不同反应气氛对载体和催化剂上NOx 存储性能的影响 .结果表明 ,NO2 较NO更易被存储 ,Pt的催化作用加速了NO的氧化反应 ,提高了催化剂的存储能力 .在 35 0℃下 ,NOx 的存储能力随着Mg/Al比的增加而升高 ,Mg和Al之间存在着协同作用 ,Al的加入有利于NOx 的存储 .低于 30 0℃时 ,Al对NOx 存储的促进作用更为显著 .n(Mg) /n(Al) =3的催化剂在 15 0～ 4 0 0℃间有较高的存储能力 ,且 30A series of Pt/Mg-Al-O catalyst samples with different Mg/Al molar ratios were prepared by coprecipitation followed by impregnation, and the catalyst samples were characterized by XRD and TPD. The effects of reaction conditions on NO x storage over the support and the catalyst were studied. The results showed that NO 2 storage was more preferable to NO storage. Pt could catalyze the oxidation of NO, resulting in much higher NO x storage capacity. The NO x storage capacity at saturation increased with the increase of Mg/Al molar ratio at 350 ℃, there was an interaction between Mg and Al, and the addition of Al 2O 3 was advantageous to the storage of NO x. The promoting effect of Al 2O 3 was more pronounced at low temperature (<300 ℃). The catalyst with n(Mg)/ n(Al)=3 possessed good performance for NO x storage in the range from 150 to 400 ℃ and had a maximum at 300 ℃.

关 键 词：氮氧化物 铂 氧化镁 氧化铝 水滑石 稀薄燃烧 Pt/Mg-AI-O催化剂 存储性能 

分 类 号：O643.3[理学—物理化学]