Effect of cobalt on the activity of iron-based catalysts in water gas shift reaction

Abstract

The water gas shift reaction (WGSR) is an important step in the commercial prodution of high pure hydrogen for several applications. In order to find alternative catalysts to this reaction, the effect of cobalt on the activity of iron-based catalysts was studied in this work. It was found that cobalt changed the properties of iron oxide depending on its content. In small amounts (Co/Fe(molar)= 0.05), it did not affect significantly the specific surface area but decreased the catalytic activity, a fact which can be assigned to the production of a cobalt and iron phase, less active in WGSR than magnetite. In higher amounts (Co/Fe= 1.0), cobalt led to an increase of specific surface area and to the production of cobalt ferrite and Co3Fe7 alloy, which was more active and more resistant against reduction than magnetite. This catalyst can probably work under low steam conditions, decreasing the operational costs.