Decomposition of Ammonia and Reactivity of Nitrogen Absorbed on Molybdenum

Abstract Adsorption measurements during the course of ammonia decomposition over molybdenum catalyst have been carried out in a closed circulating system. It was found that most of the nitrogen produced was taken up by molybdenum, and the initial rate of the reaction was independent of the ammonia pressure in a certain region. During the decomposition the nitrogen uptake was several times as much as the amount required to saturate the catalyst surface, which indicates the formation of nitride layers. The catalytic activity of molybdenum trioxide for ammonia decomposition was also observed, and the formation of nitride layers was again suggested. The nitrogen sorbed on molybdenum was removed as ammonia by admitting hydrogen and was displaced by oxygen added afterwards.