Thermal reduction of NO by NH3: Kinetic modeling of the NH2+NO product branching ratio

摘要: The product-branching ratio for the reaction NH 2 +NO→HN +OH (1) and N +H O (2) has been determined in temperature range of 950–1200 K by pyrolysis Ar-diluted 3 +NO mixtures at 1173 1200 −NO−CO mixtures. Analysis pyrolyzed unpyrolyzed was carried out FTIR spectrometric method. Kinetic modeling decay rates NO production rate CO varying branching ratio, α 1 =k /(k +k ) , keeping known total constant ( k t =9.6×10 14 T −0.85 cm mol −1 s unchanged each allows determination value with good reproducibility. using previously measured H formation data [28] from 1123–1273 also out. found to increase rapidly 0.27 950 0.58 1273 K, which is fully consistent sharply rising trend recently reported −NO flame studies, ∼0.5 1500 rose 0.9 2000 K. These new findings cast doubt on much lower values, ≤0.17 ≤1173 obtained laser kinetic measurements.