Dependence of N2O/NO Decomposition and Formation on Temperature and Residence Time in Thermal Reactor

Nitrogen dioxide (N2O) is a greenhouse gas that is harmful to the ozone layer and contributes to global warming. Many other nitrogen oxide emissions are controlled using the selective non-catalytic reaction (SNCR) process, but N2O reduction methods are few. To avoid future air pollution problems, N2O reduction from industrial sources is essential. In this study, a N2O decomposition and NO formation under an argon atmospheric N2O gas mixture were observed in a lab-scale SNCR system. The reaction rate and mechanism of N2O were calculated using a reaction path analyzer (CHEMKIN-PRO). The residence time of the gas mixture and the temperature in the reactor were set as experimental variables. The results confirmed that most of the N2O was converted to N-2 and NO. The change in the N2O reduction rate increased with the residence time at 1013 and 1113 K, but decreased at 1213 K due to the inverse reaction. NO concentration increased with the residence time at 1013 and 1113 K, but decreased at 1213 K owing to the conversion of NO back to N2O.

Automated summary

Nitrogen dioxide (N2O) is a harmful greenhouse gas that contributes to global warming, and reducing industrial emissions of N2O is essential to prevent future air pollution problems. Experimental results demonstrated that most N2O can be converted into N-2 and NO through a SNCR system, and the reduction rate is closely related to reaction temperature and residence time.