储氧量及空燃比对钯催化剂选择氧化CH_4和CO的影响  

Effect of Oxygen Storage Capacity and Air-fuel Ratio on Selective Oxidation of CH_4 and CO for Mixed Oxides Supported Palladium Catalysts

作　　者：顾永万[1,2] 彭金辉[1] 朱敬芳 张利波[1] 缪曙霞 廖康 曾超 马泽江 

机构地区：[1]昆明理工大学冶金与能源工程学院,昆明650093 [2]昆明贵研催化剂有限责任公司,昆明650106 [3]重庆长安汽车有限公司,重庆400023

出　　处：《贵金属》2015年第4期1-8,共8页Precious Metals

基　　金：国家科技支撑计划项目(2012BAE06B00)

摘　　要：制备了Pd/AlLaZrTiO_x(Pd/A),Pd/AlCeZrLaO_x(Pd/CZ)和Pd/(AlLaZrTiO_x+AlCeZrLaO_x)(Pd/CZA)3种催化剂,用热分析仪测试其储氧值(OSC),用红外光谱仪测试在过量空气系数(α)分别为0.8、1.0和1.4时3种催化剂对CH_4和CO的选择氧化性能。结果表明,催化剂的储氧性能和空燃比氛围均对CH4和CO的选择氧化性能有较大影响。储氧能力较差的Pd/A和Pd/CZA催化剂在α=1(理论空燃比)时有利于CH_4的催化燃烧,在α=1.4(富氧条件)时对CO的完全氧化有利;储氧能力较好的Pd/CZ催化剂对CH_4的催化燃烧和CO的完全氧化均在α=1左右时比较有利。贫氧条件下,Pd/CZ催化剂有利于CH_4的催化燃烧和CO的完全氧化;富氧条件下,Pd/CZA催化剂有利于CH_4的催化燃烧和CO的完全氧化;在理论空燃比附近,Pd/A催化剂对CH_4的催化燃烧较好,Pd/CZ催化剂对CO的完全氧化较好。Three Pd/AlLaZrTiOx（Pd/A）,Pd/AlCeZrLaOx（Pd/CZ） and Pd/（AlLaZrTiOx＋ AlCeZrLaOx）（Pd/CZA） catalysts were prepared and their oxygen storage capacity（OSC） was tested by thermogravimetric analyzer（TG）.Infrared spectrum analyzer was used to evaluate the selective oxidation performance of CH4 and CO by these catalysts when the excess air coefficient（α） was 0.8,1.0 and 1.4,respectively.The results show that OSC of the catalysts and air-fuel ratio for selective oxidation of CH4 and CO greatly affect the catalytic activity.Pd/A and Pd/CZA catalysts with poor OSC facilitate the catalytic combustion of CH4 at α=1（theory air-fuel ratio） and lead to the complete oxidation of CO atα=1.4（lean burn condition）,while Pd/CZ catalyst with good OSC show great catalytic activity when α is about 1.Pd/CZ catalyst should be used for catalytic combustion of CH4 and CO under the condition of the poor oxygen,whereas Pd/CZA catalyst is selected under the condition of rich oxygen or near the theory air-fuel ratio.Pd/A catalyst is more suitable for the catalytic combustion of CH4,however for the oxidation of CO,Pd/CZ shows superiority to Pd/A.

关 键 词：工业催化 钯催化剂 复合物 甲烷 CO 空燃比 储氧量 选择氧化 

分 类 号：O643.3[理学—物理化学] TK431[理学—化学]