The noble metal ( Pt and Pd) monolithic catalysts coating with rare earth elements were prepared by means of slurry coating and impregnation methods through the orthogonal experiment design and the change of the calcinating temperature of the loaded noble metal, the content of the noble metal and the Pt/Pd mass ratio. The physical and chemical properties of the catalysts were characterized with Brunauer Emmett Teller ( BET) and Scanning Electron Microscope ( SEM) analysis methods. In a constant-pressure continuous-flow fixed-bed reactor, the performance of the catalysts prepared under above-mentioned conditions and the impact of the space velocity on the performance of the catalysts were systematically investigated with the ventilation air methane. The experimental results showed that the optimum preparation conditions for the catalysts were the calcinating temperature of 750 ℃, the noble metal content of 1. 41 kg/m3 and the Pt/Pd mass ratio of 6 : 1. Under the conditions of the space velocity of 40000 h-1 and the reactive temperature of 450 ℃, the conversion rate of the methane in the ventilation air can be up to 98. 9%.%通过正交实验设计,改变负载贵金属焙烧温度、贵金属含量和铂钯质量比,采用浆料涂覆法和浸渍法制备了含有稀土元素涂层的铂、钯贵金属整体式催化剂.借助于BET和SEM分析方法对催化剂的物理化学性质进行了表征.在常压连续流动固定床反应器中,用乏风瓦斯系统地考察了上述3种制备条件下的催化剂性能,以及空速对催化剂性能的影响.实验结果表明,催化剂的最佳制备条件为:负载贵金属焙烧温度750℃,贵金属含量1.41 kg/m3,铂钯质量比6:1.在空速为40000 h-1、反应温度为450℃条件下,乏风中甲烷转化率可达98.9%.
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