Ceria-zirconia supported Pt-Fe bimetallic catalyst for water gas shift reaction with suppressed methanation activity in reformate-simulated gas

Abstract

PtFe/Ce_0.75Zr_0.25O₂ catalysts were prepared using deposition and impregnation techniques and tested in water gas shift reaction in reformate-simulated feed gas. For the catalyst prepared by subsequent deposition of the metals it was observed that iron (mole ratio Pt:Fe ≈ 1.5) provides for inhibition of side reaction of methanation at the temperatures up to 350 °C. The water gas shift reaction rate per Pt surface area was also increased compared to the catalyst without iron (Pt content was the same). XPS analysis of PtFe/Ce_0.75Zr_0.25O₂ showed that there are Pt⁰ and Fe²⁺ cations on the surface in H₂ atmosphere at 150–350 °C. In situ DRIFTS results demonstrated stronger CO adsorption on the Pt-support interfacial sites and higher CO₂ formation rate in the gas phase going from Pt to Pt-Fe system.