钡、钾、镧、铈对Co/C合成氨催化剂性能的影响

A series of Co/C ammonia synthesis catalysts promoted with Ba, K, La and Ce, were prepared by incipient-wetness impregnation method. The influnence of promoters loading and recation parameters on the catalystic activity were investigated in a fixed-bed microreactor. The experimental results indicated that the relation between the promoters loading and catalystic activity presented a volcano type curve, Ba promoter was the most effective one, and the rank was Ba＞Ce＞La＞K, the optimum molar ratio of Ba to Co atoms was 0.8. Better activity can be obtained for Co/C catalyst with bi-promoters, ammonia synthesis activity over Ce0.3-Ba0.8-Co/C catalyst can reach 6. 56 μmol/(s•g) under 12 000 h^(-1), 440℃ and atmospheric pressure.