CeO2-Al2O3负载金催化剂用于水煤气变换反应的催化活性

采用浸渍法和沉积 沉淀法制备了CeO₂-Al₂O₃复合氧化物，比较了复合氧化物负载纳米金催化剂对水煤气变换反应的催化活性。通过N2物理吸附、XRD、TEM、H₂-TPR等表征手段对复合氧化物及其负载金催化剂的物相和结构进行分析，发现复合氧化物的制备方法及其焙烧温度对其比表面积、孔结构及水煤气变换反应活性有明显的影响。与沉积 沉淀法相比，浸渍法制备的CeO₂-Al₂O₃复合氧化物具有较大的CeO₂晶粒尺寸，经500℃焙烧后再负载金，所得催化剂具有更高的活性，250℃时CO转化率可达78.1%。

Preparation of ceria-alumina and |catalytic activity of gold catalyst supported on ceria-alumina for water gas shift reaction

Ceria-alumina composite oxides with different ceria loadings (5%, 10%, 20%, 25%, and 30%) were prepared by impregnation method and deposition-precipitation method, respectively. Gold catalysts supported on these oxides were used to water gas shift reaction. All samples were characterized by nitrogen adsorption, X-ray diffraction (XRD), transmission electron microscopy (TEM) and hydrogen temperature programmed reduction (H₂-TPR). It is found that the preparation method and calcination temperature of ceria-alumina oxides have a marked influence on their surface areas, porous structures and the catalytic performances of supported gold catalysts for water gas shift reaction. Ceria-alumina oxides prepared with impregnation method gave larger ceria particle size and high catalytic activity than those prepared with deposition precipitation method. Gold catalyst supported on 20%CeO₂-Al₂O₃ oxide calcined at 500℃ showed the highest activity. CO conversion reached 78.1% at 250℃ and atmospheric pressure.