ON THE INTERACTION OF N-2 AND H-2 WITH RU CATALYST SURFACES

A series of ruthenium NH3 synthesis catalysts with selected promoters added have been studied. It is demonstrated that the rate of N-2 chemi sorption can be strongly enhanced by preadsorbed hydrogen. The promote rs La and Ba have a weak influence on the rate of N-2 dissociation on the hydrogen free surface, while they cause the rate to increase for a partly hydrogen covered surface. This increase correlates with the ef fect on the rate of NH3 synthesis. In contrast, Cs was able to increas e the rate of N-2 dissociation by two to three orders of magnitude wit h almost no change in the activity for NH3 synthesis.