Iron-molybdenum oxide catalyst mechanism

As mentioned earlier, the multicomponent oxide catalysts currently commercialized contain bismuth, iron, and molybdenum, in addition to several other cations. Although few reports concerning multicomponent catalysts have appeared in the literature, there is agreement that iron affects several aspects of the catalyst system. Measurements on multicomponent catalysts by Wolfs et al. (109-111) showed that Fe3+ was partially reduced to Fe2+ after the catalytic reaction, indicating that Fe3+ ions are involved in the reaction mechanism. The observed Fe3+/Fe2+ redox couple was associated with the increased activity of the catalyst. 

We are investigating bifunctional catalysts in which one component of the catalyst adsorbs or oxidizes CO and the other component dissociates water. Our present research is focusing on metal-support combinations to promote this bifunctional mechanism. The metallic component is chosen to adsorb CO at intermediate adsorption strengths (platinum [Pt], Ru, palladium [Pd], PtRu, PtCu, cobalt [Co], ruthenium [Ru], silver [Ag], iron [Fe], copper [Cu], and molybdenum [Mo]). The support is chosen to adsorb and dissociate water, typically a mixed-valence oxide with redox properties or oxygen... 

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