| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 4439954 | Atmospheric Environment | 2011 | 7 Pages |
In the atmosphere, alkyl nitrates formed from the reactions of alkyl peroxy radicals with NO are chemically removed by photolysis and by reaction with OH radicals. Products of the gas-phase reactions of OH radicals with 2-propyl nitrate, 3-methyl-2-butyl nitrate and 3-methyl-2-pentyl nitrate at room temperature have been investigated. The products observed and quantified were: from 2-propyl nitrate, acetone (58 ± 18%); from 3-methyl-2-butyl nitrate, acetaldehyde (113 ± 39% from gas chromatographic analyses and 70 ± 25% from FT-IR analyses), acetone (55 ± 8%), and 3-methyl-2-butanone (17 ± 2%); and from 3-methyl-2-pentyl nitrate, acetaldehyde (120 ± 26% from gas chromatographic analyses and 80 ± 21% from FT-IR analyses), propanal (≤1.1%), 2-butanone (33 ± 3%), 2-methylbutanal (≤1.1%), and 3-methyl-2-pentanone (9 ± 1%), where the percentage molar yields are given in parentheses. Using these measured product yields together with predicted reaction schemes indicates that these products account for 58 ± 18%, 86 ± 15% and 63 ± 7% of the overall reaction pathways of the 2-propyl nitrate, 3-methyl-2-butyl nitrate and 3-methyl-2-pentyl nitrate reactions, respectively. The NO2 present in the −ONO2 group in these nitrates will be released in the reaction pathways leading to the observed products.
Research highlights► Products from reaction of OH radicals with branched alkyl nitrates indicate that NO2 is released to a large extent. ► This is because the intermediate alkoxy radicals mainly decompose to form α-nitrooxy radicals which eliminate NO2. ► Alkoxy radical reactions determine whether or not the NOx in the alkyl nitrate will be released by OH radical reaction.
