Study on the Influence of Hydrothermal Parameters on Low-Temperature Denitrification of Mo-Modified Rare Earth Tailings

Abstract

Vanad-based catalysts have been widely used in NH₃-SCR denitrification technology, but their prices are expensive and the active ingredients are toxic, so the preparation of green and cheap denitrification catalysts has become the key to this technology. Natural minerals have become the focus of denitrification catalyst research because of their advantages of large reserves, low price, and environmental protection. A large number of rare earth tailings have brought great pressure to the ecological environment, and the elements that are rich in Fe, Ce, and other elements conducive to catalytic denitration have not been effectively utilized. In this paper, 7.5 wt % Mo/magnetic separation of rare earth tailings was taken as the object. In order to further improve the denitration efficiency of the catalyst and broaden the reaction temperature window, the hydrothermal reaction time and hydrothermal reaction temperature of the catalyst were adjusted during the preparation process. XRD, SEM-EDS, BET, H₂-TPR, NH₃-TPD and other characterization methods were used to study their effects on the performance of Mo-modified rare earth tailings catalysts. The study results not only provided a theoretical basis for the high-value utilization of magnetic separation rare earth tailings but also expanded the range of raw materials for NH₃-SCR denitrification catalysts.