Kinetics and reaction mechanism in the oxidation of ethyl formate in the presence of NO2: Atmospheric implications

FABIO E. MALANCA*; JUAN C. FRAIRE; GUSTAVO A. ARGÜELLO

JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY

Elsevier

Lugar: Holanda; Año: 2009 vol. 204 p. 75 - 81

1010-6030

The mechanism for the Cl-initiated oxidation of ethyl formate (EF) has been determined in the presence of NO2. The Cl atom initiates the oxidation mainly at two different sites of the molecule; one corresponds to the H-atomabstraction on the carbon atomin the-position of the oxygenated carbonylic group (62±7)% and the second to the H-atom on the carbonylic group (44±5)%. The quantification of products, within experimental uncertainties, accounts for the complete disappearance of EF. The attack of Cl atoms to the methyl group, if occurring at all, should provide for less than (2±1)%. The progress of the reaction was followed by FTIR. The oxidation reaction carried out in the presence of NO2 led to the formation of formic acid, peroxyacetyl nitrate (CH3C(O)OONO2), ethyl nitrate (CH3CH2ONO2), acetic formic anhydride (CH3C(O)OC(O)H), 1-(nitrooxy) ethyl formate and the new peroxynitrate, peroxy ethoxyformyl nitrate (CH3CH2OC(O)OONO2, PEFN), whose thermal stability at room temperature was also measured.  The Cl atom initiates the oxidation mainly at two different sites of the molecule; one corresponds to the H-atomabstraction on the carbon atomin the-position of the oxygenated carbonylic group (62±7)% and the second to the H-atom on the carbonylic group (44±5)%. The quantification of products, within experimental uncertainties, accounts for the complete disappearance of EF. The attack of Cl atoms to the methyl group, if occurring at all, should provide for less than (2±1)%. The progress of the reaction was followed by FTIR. The oxidation reaction carried out in the presence of NO2 led to the formation of formic acid, peroxyacetyl nitrate (CH3C(O)OONO2), ethyl nitrate (CH3CH2ONO2), acetic formic anhydride (CH3C(O)OC(O)H), 1-(nitrooxy) ethyl formate and the new peroxynitrate, peroxy ethoxyformyl nitrate (CH3CH2OC(O)OONO2, PEFN), whose thermal stability at room temperature was also measured.  The Cl atom initiates the oxidation mainly at two different sites of the molecule; one corresponds to the H-atomabstraction on the carbon atomin the-position of the oxygenated carbonylic group (62±7)% and the second to the H-atom on the carbonylic group (44±5)%. The quantification of products, within experimental uncertainties, accounts for the complete disappearance of EF. The attack of Cl atoms to the methyl group, if occurring at all, should provide for less than (2±1)%. The progress of the reaction was followed by FTIR. The oxidation reaction carried out in the presence of NO2 led to the formation of formic acid, peroxyacetyl nitrate (CH3C(O)OONO2), ethyl nitrate (CH3CH2ONO2), acetic formic anhydride (CH3C(O)OC(O)H), 1-(nitrooxy) ethyl formate and the new peroxynitrate, peroxy ethoxyformyl nitrate (CH3CH2OC(O)OONO2, PEFN), whose thermal stability at room temperature was also measured.