Kinetics of dissociative recombination of free electrons with hydronium ions in premixed flames

Abstract

The rate coefficient for the gas phase recombination of H₃O⁺ ions and free electrons in H₃O⁺+ e^–→ neutral products has been measured in atomospheric pressure flames of H₂+ O₂+ N₂ over the temperature range 2025–2445 K. Concentrations of ions were arrived at by sampling each flame into a mass spectrometer. The recombination coefficient was not found to vary significantly with temperature, being 4.1 ± 1.0 × 10^–7 ion^–1 cm³ s^–1 over this temperature range. This corresponds to a cross-section (πσ²) for the process of about 1.5 × 10^–18 m².