中文摘要：

氧化镁为载体的钌基氨合成催化剂具有潜在的工业应用前景，已引起了人们极大的关注．制备了5种钌基催化剂Ru／MgO、Ru／7-A1203、K-Ru／MgO、Ba-Ru／MgO和K—Ba—Ru／MgO，在V（N2）：V（H2）=1：3，2．0MPa，24000h^-1和653-873K反应条件下，评价了它们的合成氨催化活性，并对相关催化剂进行了BET和XRD表征．结果表明；Ru／MgO的最高活性约为Ru／γ-Al2O3的2倍，且最高活性反应温度还低了20K；Ba组份的添加有利于降低Ru／MgO基催化剂的最高活性温度；K-Ba-Ru／MgO在653K、Ba—Ru／MgO在773K、K—Ru／MgO和Ru／MgO在813K以上使用时，将更有利于催化活性的发挥．因此，对于Ru／MgO基催化剂而言，促进剂的添加应根据拟采用的操作温度来决定．

英文摘要：

The ruthenium-based catalyst supported on magnesia for ammonia synthesis has attracted a great attention since it exhibi- ted a potential prospect for industrial application. The ruthenium-based catalysts, Ru/MgO, Ru/γ -Al2O3, K-Ru/MgO, Ba-Ru/MgO and K-Ba-Ru/MgO were prepared and their ammonia synthesis activities were evaluated under reaction conditions of V（N2 ） ： V（H2） =1 ： 3,2.0 MPa,24 000 h-1 and 653~873 K. The relative catalysts were characterized by special surface measurement （BET） and X-ray diffraction spectroscopy （XRD）. The results show that the maximum activity of Ru/MgO is about twice of that of Ru/γ-Al2O3 and the reaction temperature is lower 20 K than the Ru/γ-Al2O3. The barium component is favorable for lowering the reaction temperature of the Ru/MgO-based catalysts with the maximum activity. In order to play extremely the catalytic activities,the better operation temperature is 653 K for K-Ba-Ru/MgO, 773 K for Ba-Ru/MgO and over 813 K for K-Ru/MgO and Ru/MgO, respectively. It is suggested that the addition of promoters should be decided by the desired operation temperatures for the Ru/MgO-based catalysts.