Initial Period of NO−NH3 Reaction over a Heat-Treated Pitch-Based Active Carbon Fiber

Abstract

The initial period of NO−NH3 reaction within 2−6 h over a heat-treated activated carbon fiber (ACF) was studied at several reaction temperatures to clarify the material balances during the complete removal of NO in this period. NO was found to be reduced and adsorbed of the ACF during the period to achieve the complete removal. NO adsorption to reach saturation decreased the initial conversion to the stationary one. Adsorbed NO provided desorption at the two temperature ranges, suggesting two species over the ACF. The species of higher temperature desorption appears to originate from NO2 species. Both species appear to be reduced with NH3. The influences of the reaction temperature and humidity on both reduction and adsorption of NO in the initial period were also observed. Competitive adsorption of NO against H2O over the ACF appears to reduce the amounts of both reduction and adsorption.