负载型贵金属催化剂用于汽车尾气净化的实验研究

Study on Supported Noble Metal Catalysts for Automobile Emission Control

以金属氧化物及稀土元素为助剂 ,以蜂窝状堇青石陶瓷为载体的贵金属催化剂 ,用于汽车尾气中CO、烃类 (HC)氧化反应 ,经比较 ,Pd Ce Ba催化剂具有低起燃温度、高效、热稳定好的特点 .对CO、烃类 (HC)氧化的起燃温度和完全氧化温度分别约为 12 0、16 0和140、190℃ .稀土元素和碱金属在催化剂表面的富聚和在活性氧化铝涂层中的存在 ,对其它活性组分起到分散、隔离和稳定的作用 。

WT5BZ]Influences of alkaline_earth metal, rare_earth elements on the catalytic activity for CO and HC oxidation for automobile emission control over a series of supported Pd oxide catalysts are reported. By comparison, a good catalyst of Pd_Ce_Ba which displays high catalytic activity and good thermal durability for CO and HC emission was singled out. On the catalyst, its ignition temperature for CO and hydrocarbons (HC) are 120 ℃, 160 ℃ and its light_off temperatures are 140 ℃, 190 ℃ respectively. The enrichment of rare_earth elements Ce and alkaline_earth metal Ba on the surface of the catalyst and their presence in the active aluminium oxide coating give rise to the dispersion, isolation and stabilization of Pd active components, thus ensuring good thermal durability for the catalyst.