Influence of the tungsten oxide precursor on WOxsingle bondZrO2 and Pt/WOxsingle bondZrO2 properties Original Research Article

The influence of the tungsten precursor and of the preparation conditions on the properties of platinum free or platinum containing WOx promoted zirconia has been studied. Catalysts were characterized by hydrogen chemisorption at room temperature, TPR, XRD and Laser Raman spectroscopy and during the n-hexane reaction at 200°C, 6 kg cm−2, and a hydrogen/n-hexane molar ratio 7. For all catalysts, the same WOx species were observed after calcination: crystalline WO3 and an amorphous WOx species were detected by Laser Raman. The best catalytic activity and stability were observed on catalysts in which platinum was added after calcination, independently of the WOx precursor used in the preparation.