Model of active surface of iron catalyst for ammonia synthesis

Abstract

The AES method has been used to investigate the iron-potassium-oxygen system. A new model of the iron catalyst for the ammonia synthesis reaction has been proposed, on the grounds of studies on the interactions between potassium, oxygen, and nitrogen on the iron surface. In this simple model the active sites are located under the layer of potassium atoms and on the layer of iron atoms. A part of those sites are occupied by oxygen atoms which stabilize the potassium atoms on the catalyst surface at the temperature of the ammonia synthesis reaction. The promoting action of potassium in this reaction is effected by the electron transfer from potassium to the iron surface covered with oxygen.