NO<sub>3</sub> chemistry of wildfire emissions: a kinetic study of the gas-phase reactions of furans with the NO<sub>3</sub> radical
<p>Furans are emitted to the atmosphere during biomass burning from the pyrolysis of cellulose. They are one of the major contributing volatile organic compound (VOC) classes to OH and NO<span class="inline-formula"><sub>3</sub></span> reactivity in biomass bu...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2022-02-01
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| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://acp.copernicus.org/articles/22/1761/2022/acp-22-1761-2022.pdf |
| Summary: | <p>Furans are emitted to the atmosphere during biomass burning from
the pyrolysis of cellulose. They are one of the major contributing volatile organic compound (VOC) classes to OH and NO<span class="inline-formula"><sub>3</sub></span> reactivity in biomass burning plumes. The major
removal process of furans from the atmosphere at night is reaction with the
nitrate radical, NO<span class="inline-formula"><sub>3</sub></span>. Here, we report a series of relative rate
experiments in the 7300 L indoor simulation chamber at Institut de Combustion Aérothermique Réactivité et Environnement, Centre national de la recherche scientifique (ICARE-CNRS),
Orléans, using a number of different reference compounds to determine
NO<span class="inline-formula"><sub>3</sub></span> reaction rate coefficients for four furans, two furanones, and
pyrrole. In the case of the two furanones, this is the first time that
NO<span class="inline-formula"><sub>3</sub></span> rate coefficients have been reported. The recommended values
(cm<span class="inline-formula"><sup>3</sup></span> molec.<span class="inline-formula"><sup>−1</sup></span> s<span class="inline-formula"><sup>−1</sup></span>) are as follows: furan, (1.49 <span class="inline-formula">±</span> 0.23) <span class="inline-formula">×</span> 10<span class="inline-formula"><sup>−12</sup></span>; 2-methylfuran, (2.26 <span class="inline-formula">±</span> 0.52) <span class="inline-formula">×</span> 10<span class="inline-formula"><sup>−11</sup></span>; 2,5-dimethylfuran, (1.02 <span class="inline-formula">±</span> 0.31) <span class="inline-formula">×</span> 10<span class="inline-formula"><sup>−10</sup></span>;
furfural (furan-2-aldehyde), (9.07 <span class="inline-formula">±</span> 2.3) <span class="inline-formula">×</span> 10<span class="inline-formula"><sup>−14</sup></span>; <span class="inline-formula"><i>α</i></span>-angelicalactone (5-methyl-2(3H)-furanone), (3.01 <span class="inline-formula">±</span> 0.45) <span class="inline-formula">×</span> 10<span class="inline-formula"><sup>−12</sup></span>; <span class="inline-formula"><i>γ</i></span>-crotonolactone (2(5H)-furanone), <span class="inline-formula"><i><</i>1.4</span> <span class="inline-formula">×</span> 10<span class="inline-formula"><sup>−16</sup></span>; and pyrrole, (6.94 <span class="inline-formula">±</span> 1.9) <span class="inline-formula">×</span> 10<span class="inline-formula"><sup>−11</sup></span>. The furfural <span class="inline-formula">+</span> NO<span class="inline-formula"><sub>3</sub></span> reaction rate coefficient is found to
be an order of magnitude smaller than previously reported. These experiments
show that for furan, alkyl-substituted furans, <span class="inline-formula"><i>α</i></span>-angelicalactone,
and pyrrole, reaction with NO<span class="inline-formula"><sub>3</sub></span> will be the dominant removal process at
night and may also contribute during the day. For <span class="inline-formula"><i>γ</i></span>-crotonolactone,
reaction with NO<span class="inline-formula"><sub>3</sub></span> is not an important atmospheric sink.</p> |
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| ISSN: | 1680-7316 1680-7324 |