The performance of catalyst's preferential oxidation(PROX) of CO is studied based on the characterization for the macroporous monolithic CuO-CeO2/Al2O3catalysts by SEM,XRD and H2-TPR,which are prepared by impregnation method following the preparation of macroporous monolithic Al2O3support by calcination method based on a polystyrene template and by filling alumina sol. The characterization results show that CuO in the catalysts is highly dispersed mainly in the form of aggregates with particle sizes 200 nm uniformly distributed on the pore wall of the support;the catalysts can reduce the concentration of CO in the hydrogen-rich gas to less than 100×10-6at the temperature range of 140-160 ℃ and the GHSV of 21 000 h-1. This approach makes it possible to miniaturize reactors. In addition,the macroporous monolithic CuO-CeO2/Al2O3catalysts are featured by lower diffusional limitation due to their thin active component load and extended pores(more curved),and the selectivity of the catalysts is greater than that of crushed ones,which indicates that the catalysts are still featured by diffusion resistance and there is still room for improvement.%以聚苯乙烯为模板剂,通过填充铝溶胶,焙烧制备了大孔结构-整体式Al2O3载体,再通过浸渍法制备大孔结构-整体式CuO-CeO2/Al2O3催化剂,利用SEM,XRD,H2-TPR等方法对催化剂进行表征,考察了催化剂的CO优先氧化(PROX)性能.表征结果显示,大孔结构-整体式CuO-CeO2/Al2O3催化剂中CuO处于高分散状态,主要以粒径为200 nm的聚集体均匀分布在载体孔壁上;催化剂用于PROX过程中时,在反应温度140~160 ℃,气态空速21000 h-1下可将富氢气体中CO浓度降低至100×10-6以下.该方法可实现反应器的小型化.大孔结构-整体式CuO-CeO2/Al2O3催化剂的活性组分负载厚度薄,孔道四通八达(更弯曲),具有更低的扩散限制;催化剂的选择性大于破碎后的催化剂,说明催化剂仍然存在扩散阻力,具有改进的空间.
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