Kinetics and Mechanism of Ammonia Synthesis

Abstract Synthesis of ammonia on iron catalysts was discovered in 1905. Five years later, an iron catalyst containing two promoters, alumina and potassium oxide, was invented by a team of Badische Anilin und Soda Fabrik (BASF). The first high-pressure ammonia plant went on stream in 1913. Thus it took only 8 years between discovery, invention, and innovation, a remarkable record considering the novelty at the time of high-pressure operation 1. Also noteworthy is the fact that the original BASF iron catalyst is still in use today although additional promoters are added to the two original ones in various commercial formulations 2. In fact, recent advances in ammonia manufacture have been largely of an engineering nature 3. This is so in spite of a very large amount of fundamental and applied work designed to elucidate the mechanism of the reaction and the surface chemistry of commercial or alternative catalysts.