Selective catalytic reduction of NO x by low-temperature NH3 over Mn x Zr1 mixed-oxide catalysts

Shuaibo Zhang; Haixia Li; Anchao Zhang; Zhijun Sun; Xinmin Zhang; Changze Yang; Leying Jin; Zhiheng Song

doi:10.1039/d1ra08800a

Selective catalytic reduction of NO _x by low-temperature NH₃ over Mn _x Zr₁ mixed-oxide catalysts

RSC Adv. 2022 Jan 6;12(3):1341-1351. doi: 10.1039/d1ra08800a. eCollection 2022 Jan 5.

Authors

Shuaibo Zhang¹, Haixia Li¹, Anchao Zhang¹, Zhijun Sun¹, Xinmin Zhang¹, Changze Yang¹, Leying Jin¹, Zhiheng Song¹

Affiliation

¹ School of Mechanical and Power Engineering, Henan Polytechnic University Jiaozuo 454000 China lihx@hpu.edu.cn.

Abstract

Mn _x Zr₁ series catalysts were prepared by a coprecipitation method. The effect of zirconium doping on the NH₃-SCR performance of the MnO _x catalyst was studied, and the influence of the calcination temperature on the catalyst activity was explored. The results showed that the Mn₆Zr₁ catalyst exhibited good NH₃-SCR activity when calcined at 400 °C. When the reaction temperature was 125-250 °C, the NO _x conversion rate of Mn₆Zr₁ catalyst reached more than 90%, and the optimal conversion efficiency reached 97%. In addition, the Mn₆Zr₁ catalyst showed excellent SO₂ and H₂O resistance at the optimum reaction temperature. Meanwhile, the catalysts were characterized. The results showed that the morphology of the MnO _x catalyst was significantly changed, whereby as the proportion of Mn⁴⁺ and O_α species increased, the physical properties of the catalyst were improved. In addition, both Lewis acid sites and Brønsted acid sites existed in the Mn₆Zr₁ catalyst, which reduced the reduction temperature of the catalyst. In summary, zirconium doping successfully improved the NH₃-SCR performance of MnO _x .