Experimental and theoretical study about sulfur deactivation of Ni/ CeO2 and Rh/CeO2 catalysts

Sulfur deactivation of Ni/CeO2 and Rh/CeO2 catalysts were examined through an experimental and theoretical study. These catalysts were characterized by N2 adsorption, X-ray diffraction, temperature programmed reaction, thermogravimetric analysis, Uv-visible spectroscopy and Raman spectroscopy, and tested under the methane dry reforming reaction in the presence of H2S. On the other hand different possible interactions of sulfur with Rh, Ni or surface sites of the CeO2 support were evaluated by performing energy calculations with the density functional theory (DFT). Our experimental and theoretical study about sulfur deactivation of Ni and Rh supported on CeO2 allow us to postulate that Rh can help to desorb SOx species formed on the support, retarding sulfur poisoning of the Rh/CeO2 catalysts.