The black rock series supported SCR catalyst for NO _x removal

Black rock series (BRS) is of great potential for their plenty of valued oxides which include vanadium, iron, alumina and silica oxides, etc. BRS was used for directly preparing of selective catalytic reduction (SCR) catalyst by modifying its surface texture with SiO₂-TiO₂ sols and regulating its catalytic active constituents with V₂O₅ and MoO₃. Consequently, 90% NO removal ratio was obtained within 300-400 °C over the BRS-based catalyst. The structure and properties of the BRS-based catalyst were characterized by the techniques of N₂ adsorption-desorption, X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), H₂-temperature programmed reduction (H₂-TPR), and NH₃-temperature programmed desorption (NH₃-TPD). The results revealed that the BRS-based catalyst possesses favorable properties for NO _x removal, including highly dispersed active components, abundant surface-adsorbed oxygen O_α, well redox property, and numerous Brønsted acid sites. Particularly, the BRS-based catalyst exhibited considerable anti-poisoning performance compared with commercial TiO₂-based catalyst. The former catalyst shows a NO conversion surpassing 80% from 300 to 400 °C for potassium poisoning, and a durability of SO₂ and H₂O exceeding 85% at temperatures from 300 to 450 °C.