A possible unaccounted source of atmospheric sulfate formation: amine-promoted hydrolysis and non-radical oxidation of sulfur dioxide.

ABSTRACT: Numerous field and laboratory studies have shown that amines, especially dimethylamine (DMA), are crucial to atmospheric particulate nucleation. However, the molecular mechanism by which amines lead to atmospheric particulate formation is still not fully understood. Herein, we show that DMA molecules can also promote the conversion of atmospheric SO₂ to sulfate. Based on ab initio simulations, we find that in the presence of DMA, the originally endothermic and kinetically unfavourable hydrolysis reaction between gaseous SO₂ and water vapour can become both exothermic and kinetically favourable. The resulting product, bisulfite NH₂(CH₃)₂ ⁺·HSO₃ ^-, can be readily oxidized by ozone under ambient con

SUBMITTER: Wang S 

PROVIDER: S-EPMC7059313 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature