N2O and CO2 Formation during Selective Catalytic Reduction of NO with NH3 over V2O5/AC Catalyst

Much research has shown that V2O5/AC is promising for the selective catalytic reduction (SCR) of NO with NH3 at low temperatures (180-250 degrees C), However, information on N2O formation and AC oxidation during the SCR process are limited especially under actual conditions in the presence of SO2 and H2O.,Thee are studied in this work through specially designed experiments. Results show that under the conditions used, V2O5 loading, reaction temperature, and SO2 concentration have limited, effects on N2O formation. N2O is generated from reduction of NO by both AC and NH3. SCR selectivity to N-2 is promoted by V2O5, and less than 1 wt.% V2O5 is sufficient to yield a N-2 selectivity of higher than 95%. Oxidation of AC to CO2 is promoted by temperature and SO2 and originates mainly from reaction of carbon-and-oxygen-containing functional groups with sulfuric acid formed from SO2 adsorption in the presence of SO2.