Open AccessEffect of Indium Addition on the Low-Temperature Selective Catalytic Reduction of NOx by NH3 over MnCeOx Catalysts: The Promotion Effect and Mechanism
Author(s) -
Changze Yang,
Haixia Li,
Anchao Zhang,
Zhijun Sun,
Xinmin Zhang,
Shuaibo Zhang,
Leying Jin,
Zhiheng Song
Publication year - 2022
Publication title -
acs omega
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.779
H-Index - 40
ISSN - 2470-1343
DOI - 10.1021/acsomega.1c07000
Subject(s) - catalysis , calcination , selective catalytic reduction , fourier transform infrared spectroscopy , indium , chemistry , crystallization , temperature programmed reduction , inorganic chemistry , thermal desorption spectroscopy , x ray photoelectron spectroscopy , coprecipitation , analytical chemistry (journal) , desorption , atmospheric temperature range , adsorption , chemical engineering , organic chemistry , physics , meteorology , engineering
A MnCeInO x catalyst was prepared by a coprecipitation method for denitrification of NH 3 -SCR (selective catalytic reduction). The catalysts were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry, scanning electron microscopy, X-ray photoelectron spectroscopy, Brunauer-Emmett-Teller analysis, H 2 temperature-programmed reduction, and NH 3 temperature-programmed desorption. The NH 3 -SCR activity and H 2 O and SO 2 resistance of the catalysts were evaluated. The test results showed that the SCR and water resistance and sulfur resistance were good in the range of 125-225 °C. The calcination temperature of the Mn 6 Ce 0.3 In 0.7 O x catalyst preparation was studied. The crystallization of the Mn 6 Ce 0.3 In 0.7 O x catalyst was poor when calcined at 300 °C; however, the crystallization is excessive at a 500 °C calcination temperature. The influence of space velocity on the performance of the catalyst is great at 100-225 °C. FTIR test results showed that indium distribution on the surface of the catalyst reduced the content of sulfate on the surface, protected the acidic site of MnCe, and improved the sulfur resistance of the catalyst. The excellent performance of the Mn 6 Ce 0.3 In 0.7 O x catalyst may be due to its high content of Mn 4+ , surface adsorbed oxygen species, high specific surface area, redox sites and acid sites on the surface, high turnover frequency, and low apparent activation energy.