In this work, pyridine-N was converted into NO and N-2 by using a flow reactor and the dominant NO evolution pathways were identified by means of a kinetic modeling under O-2/CO2 atmosphere in temperature range of 1073-1473 K for different stoichiometries. The experimental results indicated higher temperatures promoted the formation of NO, with conversions varied from 1.26-18.64% to 3.85-43% for fuel-rich and fuel-lean conditions respectively. As for N2 formation, conversion of pyridine to N-2 had a slight increase from 1073 to 1173 K then declined rapidly in oxidizing atmosphere, whereas this conversion stabilized at about 36% before decreasing to 29% above 1173 Kin the presence of insufficient O-2. Increasing the equivalence ratio led to a monotonic increase of NO in both O-2/Ar and O-2/CO2 atmospheres, and the gap between these atmospheres developed with a. The simulation results showed that the high CO2 concentration reduced the availability of oxygen thus altered the evolution of NO through promoting reaction HNO + M <-> H + NO + M and limiting reaction HNO + O-2 <-> HO2 + NO. This was even more important at higher temperatures. Besides, the major pathways for NO consumption were taken through reaction with NCO and NH as intermediates. In general, the model of Terasa09 described the experimental trends well, and this combustion kinetic was applicable to oxy-fuel conditions. (C) 2011 Elsevier Ltd. All rights reserved.