Sulfur-resistant methanation over MoO3/CeO2–ZrO2 catalyst: Influence of Ce-addition methods

In this paper, Ce 0.2 Zr 0.8 O 2 composite supports were prepared by different Ce-addition methods including impregnation of cerium (CeZr-imp), impregnation of citric acid and cerium (CeZr-CA) simultaneously and deposition precipitation method (CeZr-DP), respectively. The as-prepared supports were applied to prepare 10 wt% MoO 3 /Ce 0.2 Zr 0.8 O 2 catalysts for sulfur-resistant methanation . The N 2 adsorption/desorption, X-ray diffraction (XRD), Raman spectroscopy (RS), X-ray photoelectron (XPS), temperature-programmed reduction by hydrogen (H 2 -TPR) were undertaken to get textural properties, morphological information and structures of the catalysts. The results showed that MoO 3 was highly dispersed on the surface of these three supports and Ce was mostly of coexisted in Ce 4+ /Ce 3+ redox pairs. Compared with Mo/CeZr-imp, the CO conversion increased by 10% and 15% for Mo/CeZr-CA and Mo/CeZr-DP, respectively. This was mainly attributed to the larger specific surface area, Ce 3+ concentration and content of active MoS 2 on the surface of catalysts.