Synthesis of copper promoted high temperature water–gas shift catalysts by oxidation–precipitation

Copper promoted high temperature water–gas shift catalysts were directly synthesized in the active phase (Fe3O4) through an oxidation–precipitation (oxiprecipitation) method, avoiding the usual reduction step used to activate the catalyst in the conventional method based on coprecipitation. They were characterized using X-ray diffraction, X-ray fluorescence, infrared spectroscopy, adsorption–desorption of N2 at 77 K, transmission electron microscopy and temperature programmed reduction. Their catalytic activity was also studied. The results indicated that the materials obtained through this new synthesis method exhibited higher catalytic activity than the commercialized catalysts. Furthermore, the addition of copper improved the catalytic performance of oxiprecipitated Fe–Cr materials, increasing the reducibility of the sample and its stability under reaction conditions.