VOX supported on TiO2–Ce0.9Zr0.1O2 core–shell structure catalyst for NH3-SCR of NO

Abstract

In this experiment, a TiO₂–Ce_0.9Zr_0.1O₂ support with core–shell structure was successfully prepared by a precipitation method and VO_X/TiO₂–Ce_0.9Zr_0.1O₂ catalyst was prepared by an impregnation method, and the catalyst was used to catalyze the NH₃-SCR of NO. Based on the results of HRTEM, XRD, BET, H₂-TPR, NH₃-TPD, XPS, Py-IR, it was speculated that due to the interaction between TiO₂ and Ce_0.9Zr_0.1O₂, more oxygen vacancies and Ce³⁺ are generated, which are beneficial to the existence of low-valence V by electron transfer between high valence state V and Ce³⁺and increase the acidic sites on the catalyst surface. The catalytic activity (>97%) of the VO_X/TiO₂–Ce_0.9Zr_0.1O₂ catalyst is superior to the current commercial catalyst (V₂O₅–WO₃/TiO₂) and has a higher N₂ selectivity (>97.5%) at 40 000 h⁻¹ GHSV and 250–400 °C.