Effects of CeO_2 preparation methods on the catalytic performance of MoO_3/CeO_2 toward sulfur-resistant methanation

CeO₂ supports were prepared by calcination or precipitation method and 5% MoO₃/CeO₂ catalysts were prepared by incipient-wetness impregnation method. The catalytic performance of the 5% MoO₃/CeO₂ catalysts toward sulfur-resistant methanation was investigated. The results showed that the Mo/Ce-1 catalysts with CeO₂ support prepared by calcination method exhibited the best sulfur-resistant methanation activity and stability with CO conversion as high as 75% while the Mo/Ce-3 catalysts the poorest. The supports and catalysts were characterized by N₂-adsorption–desorption, temperature-programmed reduction (TPR), X-ray diffraction (XRD), Raman spectroscopy (RS) and scanning electron microscope (SEM). The results indicated that the saturated monolayer loading MoO₃ on Ce-3 support was lower than 5% and there were some crystalline MoO₃ particles on the surface of the Mo/Ce-3. The preparation method of CeO₂ had a big influence on the specific surface area, the crystalline of CeO₂, and the catalytic performance of the corresponding Mo-based catalyst for sulfur-resistant methanation.