Effect of ZrO2 on the performance of Co–CeO2 catalysts for hydrogen production from waste-derived synthesis gas using high-temperature water gas shift reaction

Abstract

In this study, highly active and stable CeO 2 , ZrO 2 , and Zr (1- x ) Ce ( x ) O 2 -supported Co catalysts were prepared using the co-precipitation method for the high-temperature water gas shift reaction to produce hydrogen from waste-derived synthesis gas. The physicochemical properties of the catalysts were investigated by carrying out Brunauer-Emmet-Teller, X-ray diffraction, CO-chemisorption, Raman spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and H 2 -temperature-programmed reduction measurements. With an increase in the ZrO 2 content, the surface area and reducibility of the catalysts increased, while the interaction between Co and the support and the dispersion of Co deteriorated. The Co–Zr 0.4 Ce 0·6 O 2 and Co–Zr 0.6 Ce 0·4 O 2 catalysts showed higher oxygen storage capacity than that of the others because of the distortion of the CeO 2 structure due to the substitution of Ce 4+ by Zr 4+ . The Co–Zr 0.6 Ce 0·4 O 2 catalyst with high reducibility and oxygen storage capacity exhibited the best catalytic performance and stability among all the catalysts investigated in this study. • CeO 2 , ZrO 2 , and Zr (1-x) Ce (x) O 2 -supported Co catalysts were prepared. • WGS reaction was carried out over the catalysts to produce hydrogen from syngas. • Oxygen storage capacity and reducibility were dependent on the ratio of Ce/Zr. • Co–Zr 0.4 Ce 0·6 O 2 showed the best performance among the prepared catalysts. • This performance was relating to its high oxygen storage capacity and reducibility.