1. Revealing the poisoning effect of potassium salts on MnOx catalysts for low-temperature simultaneous removal of NO and CO.
- Author
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Wang, Liang, Jiang, Yanhua, Zeng, Wen, Li, Xiaodi, Ren, Shan, He, Chi, and Yin, Xitao
- Subjects
POTASSIUM salts ,POISONING ,CATALYSTS ,CATALYST poisoning ,FLUE gases ,CATALYTIC activity - Abstract
Simultaneously elimination of NO and CO in the sintering flue gas is an urgent problem, in which the application of the bifunctional MnO x catalyst has demonstrated its effectiveness in removing NO and CO simultaneously. Potassium salts are frequently found in the sintering flue gas and exert a detrimental influence on the catalytic performance of catalysts. Herein, the primary focus of this study is to investigate different K
+ species (K 2 SO 4 , KCl, KNO 3) poisoning effect on bifunctional MnO x. The findings suggested a deactivation order in the sequence of KNO 3 > KCl > K 2 SO 4. Fresh Mn-AC catalyst had finer grains, and poisoning elements were evenly distributed. XPS results revealed an obvious decrease in Mn4+ and O β species across all catalysts after K+ species poisoning, hindering redox cycle activation and oxygen species mobility, thus impacting catalytic activity. The in situ DRIFTS results indicated the forbidden of E-R route over KNO 3 -poisoned catalysts and low reactivity of adsorbed species after poisoning for NO removal. KNO 3 severely suppressed surface reaction paths on Mn-AC catalyst and declined the catalytic efficiency, especially in CO activation. Finally, a possible reaction mechanism model for the simultaneous removal of NO and CO was proposed. This study could provide reference for the development of bifunctional catalyst with high resistance to potassium salts. • Fresh and K-poisoned Mn-AC catalysts were synthesized by combining PEG-assited co-precipitation and impregnation methods. • The poisoning sequence of Mn-AC catalyst was followed as K 2 SO 4 < KCl- Published
- 2024
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