Cold Plasma-Assisted Selective Catalytic Reduction of NO over B2O3/γ-Al2O3

Abstract A plasma-assisted catalytic system for the selective catalytic reduction of NO with methane was investigated. NO2, HCHO, CH3NO, and CH3NO2 were the reactive intermediates generated by the plasma. The further reactions of these intermediates on the catalyst during the thermal catalytic stage resulted in the conversion of NOx to N2, which was verified by temperature-programmed surface reaction characterization. B2O3γ-Al2O3 was the best catalyst with the maximum conversion of NOx to N2 increasing from 33.4% on γ-Al2O3 to 51.0% on 10 wt% B2O3γ-Al2O3 at 300 °C. NH3-TPD characterization showed that the acidity of the catalyst is important for the reduction of NOx by the intermediates generated by the plasma. NOx-TPD showed that the adsorbed NOx species on the catalysts also played a role in the conversion of NOx.

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