Experimental and numerical study of the effect of H2O and CO2 dilution on NH3/CH4 co-oxidation characteristics in a jet-stirred reactor

Abstract

This work reports an experimental and kinetic modeling study of NH3/CH4 co-oxidation in O2/N2 in a jet-stirred reactor (JSR) covering a reaction temperature of 900–1450 K, equivalence ratio of 0.5–2.0, and dilution degree of 0%–30% with H2O and CO2, respectively. Experimental results show that CO formation is inhibited by H2O dilution while enhanced by CO2 dilution. NO formation is suppressed by either H2O or CO2 dilution under lean condition, however these two diluents generally would accelerate NO formation under stoichiometric and rich conditions. Dong2022 mechanism is selected for further kinetic analysis for NO conversion under stoichiometric condition. It shows that N2H2 plays a more significant role in NO generation in N2/CO2 atmosphere. The reactions of NH + OH ↔ HNO + H and NH2 + O ↔ HNO + H contribute the most for boosting NO formation under both H2O and CO2 dilution conditions.