Abstract: The ruthenium catalyst supported on activated carbon was prepared by the impregnation method. The effect of such factors as dryness, pH value during precipitation, surface area and porosity of the activated carbons, sequence of precipitation, etc on the catalytic activity and Ru dispersion were studied during preparation. The results showed that activated carbon should be dried at 100—200 ℃ for 6—8 h before precipitation. Also, activated carbon must have enough surface area, especially the developed mesopores, which provided enough sites for Ru deposition. It was also found that the surface area and porosity of activated carbon changed greatly during precipitation. Barium promoters might provide the deposition surface for Ru, while potassium might fill in mesopore and contact with Ru, providing electrons for Ru. In order to obtain good Ru dispersion, the pH of the aqueous solution of RuCl₃•3H₂O should be controlled at 0.40—1.05, and the sequence of precipitation should be Ba-Ru-K. Only then could good performance of Ru-based ammonia synthesis catalysts be achieved.

摘要： 利用浸渍法制备了活性炭负载钌基氨合成催化剂，讨论了影响钌分散度与氨合成催化活性的若干因素. 研究发现，若活性炭载体具有较大的比表面和较好的孔结构将有利于活性组分的分散. 同时，在浸渍之前，样品需在100～200 ℃干燥6～8 h. 催化剂各组分浸渍后对载体的表面结构影响不同，实验发现，Ba的添加可能为Ru的分散提供了合适的表面，而K主要填充于载体中孔并和Ru充分接触，并为Ru提供电子.同时要控制母体钌水溶液的pH值，并选用合适的浸渍顺序，方能达到较好的效果.