Mise en evidence de la formation d'hydrogene par la reaction de recombinaison bimoleculaire des radicaux HO2. Reaction heterogene de basse temperature des radicaux HO2

Article abstract of DOI:10.1139/v82-415

It is shown that there is practically no reaction of HO2 radicals on walls of quartz or Pyrex glass, coated or not with boric acid, at temperatures higher than the ambient one, whereas at lower temperatures these radicals disappear.The rate of disappearance increases with decreasing temperature, contrary to what occurs at high temperature (t > 150 deg C).The apparent coefficient of heterogenous recombination may be expressed by γ_a=1.9x10^-11 exp(11000/RT).By using, as a new thermal source of HO2 radicals, the system O2 + 10 ppm of C7H15O-OC7H15 (t 220-240 deg C, quartz vessel coated with B2O3 and treated by the slow reaction H2/O2, HO2 radicals formed through the reaction C7H15O + O2 -> HO2 + product), it was possible to study the bimolecular recombination reaction of H2O radicals.The formation of molecular hydrogen was shown; we deduce from this that the recombination reaction produces H2O2 and H2 by two competitive paths; <*>