Promotion effect of Ce and Ta co-doping on the NH-SCR performance over VO/TiO catalyst.

NH-SCR (SCR: Selective catalytic reduction) is an effective technology for the de-NO process from both mobile and stationary pollution sources, and the most commonly used catalysts are the vanadia-based catalysts. An innovative VO-CeO/TaTiO catalyst for NO removal was prepared in this study. The influences of Ce and Ta in the VO-CeO/TaTiO catalyst on the SCR performance and physicochemical properties were investigated. The VO-CeO/TaTiO catalyst not only exhibited excellent SCR activity in a wide temperature window, but also presented strong resistance to HO and SO at 275 ℃. A series of characterization methods was used to study the catalysts, including H-temperature programmed reduction, X-ray photoelectron spectroscopy, NH-temperature programmed desorption, etc. It was discovered that a synergistic effect existed between Ce and Ta species. The introduction of Ce and Ta enlarged the specific surface area, increased the amount of acid sites and the ratio of Ce, (V+V) and O, and strengthened the redox capability which were related to synergistic effect between Ce and Ta species, significantly improving the NH-SCR activity.