The results of a 57Fe transmission and conversion electron Mössbauer spectroscopic (CEMS) study of a series of Fe-Co ammonia synthesis catalysts are reported. The catalysts were prepared by conventional coprecipitation techniques, followed by calcining, reducing and stabilisation steps. The calcined samples are multiphasic and are composed mainly of iron oxides and/or cobalt spinels. The reduced and stabilised samples are shown to consist of a Fe-Co alloy core encased in an oxide shell in which the Co/Fe ratio exceeds the Co/Fe ratio of the alloy core. It is likely that the iron-cobalt distribution in the alloy core is inhomogeneous. © 1982.
|Number of pages||13|
|Publication status||Published - 15 Jul 1982|