Thermal reduction of NO by H2: Kinetic measurement and computer modeling of the HNO + NO reaction

Wei-Guang Diau, Melissa J. Halbgewachs, Anita R. Smith, Ming-Chang Lin*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

26 Scopus citations


The kinetics and mechanism of the thermal reduction of NO by H2 have been investigated by FTIR spectrometry in the temperature range of 900 to 1225 K at a constant pressure of 700 torr using mixtures of varying NO/H2 ratios. In about half of our experimental runs, CO was introduced to capture the OH radical formed in the system with the well‐known, fast reaction, OH + CO → H + CO2. The rates of NO decay and CO2 formation were kinetically modeled to extract the rate constant for the rate‐controlling step, (2) HNO + NO → N2O + OH. Combining the modeled values with those from the computer simulation of earlier kinetic data reported by Hinshelwood and co‐workers (refs. [3] and [4]), Graven (ref.[5]), and Kaufman and Decker (ref. [6]) gives rise to the following expression: (Formula Presented.) . This encompasses 45 data points and covers the temperature range of 900 to 1425 K. RRKM calculations based on the latest ab initio MO results indicate that the reaction is controlled by the addition/stabilization processes forming the HN(O)NO intermediate at low temperatures and by the addition/isomerization/decomposition processes producing N2O + OH above 900 K. The calculated value of k2 agrees satisfactorily with the experimental result. © 1995 John Wiley & Sons, Inc.

Original languageEnglish
Pages (from-to)867-881
Number of pages15
JournalInternational Journal of Chemical Kinetics
Issue number9
StatePublished - 1 Jan 1995


Dive into the research topics of 'Thermal reduction of NO by H2: Kinetic measurement and computer modeling of the HNO + NO reaction'. Together they form a unique fingerprint.

Cite this