Study of nitrate radical (NO3) reactions with carbonyls and acids in aqueous solution as a function of temperature

P. Gaillard de Semainville , D. Hoffmann , C. George (1) , H. Herrmann

1 IRCELYON - Institut de recherches sur la catalyse et l'environnement de Lyon

Using laser photolysis experiments, the reactivity of the nitrate radical towards four carbonyl compounds and three carboxylic acids was studied. All kinetics measurements were carried out as a function of the temperature in the range from 278 K to 318 K. Furthermore, the effect of the acid–base equilibrium on the reactivity of the three acids was studied by measuring the activation parameters of the dissociated and undissociated acids at pH = 6 and pH = 0.5, respectively. The following Arrhenius expressions were obtained: Errors stated throughout this study are statistical errors for a confidence interval of 95%. The importance of the obtained results for the understanding of the tropospheric oxidation processes is discussed. The kinetics resulting from this work are compared with results for other atmospheric radicals.

Domaines: Environnement et Société; Catalyse

P. Gaillard de Semainville, D. Hoffmann, C. George, H. Herrmann. Study of nitrate radical (NO3) reactions with carbonyls and acids in aqueous solution as a function of temperature. Physical Chemistry Chemical Physics, 2007, 9, pp.958-968. ⟨10.1039/b613956f⟩. ⟨hal-00172933⟩