One-pot synthesized Cu-SSZ-13 catalyst treated with dilute HNO achieved superior activity and selectivity in the selective catalytic oxidation (SCO) of NH to nitrogen, in comparison with other zeolite-based catalysts and most of metal-oxide catalysts. Furthermore, the catalyst showed the similar or even higher catalytic activity than the partial noble-metal catalysts, and meanwhile its N selectivity was superior to most noble-metal catalysts. The characterization results demonstrated that more Cu ions existing in Cu-SSZ-13 catalyst were advantageous to its NH-SCO activity. The in situ DRIFTS results indicated that the reactivity of NH species adsorbed on Lewis and Brønsted acid sites over Cu-SSZ-13-O-H catalyst depended on the reaction temperature. The results of this study suggest the one-pot synthesized Cu-SSZ-13 is a promising NH-SCO catalyst for practical application, either mobile or stationary pollution sources.

The catalytic oxidation of NO plays an important role in the process of DeNO x . In this study, a series of Cu–Mn–O x mixed metal oxides were prepared by a co-precipitation method. The NO oxidation performances indicated that the catalyst with a Cu:Mn molar ratio of 1:1 prepared at pH 6 (denoted CuMnpH6) exhibited the best activity. In the presence of H2O, the activity of the CuMnpH6 catalyst was improved obviously compared to those of the other samples. The basicity of α-MnO2 was weakened after the addition of Cu. The basicity modification might inhibit the adsorption of H2O on surface oxygen atoms and likely promote the adsorption of NO over the CuMnpH6 catalyst. The redox properties were enhanced, and dual redox cycles existed during NO oxidation. The redox properties and surface basicity, which are related to the NO adsorption capacity, were correlated to the NO oxidation and resistance to H2O over Cu–Mn–O x catalysts.

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