On the importance of multiphase photolysis of organic nitrates on their global atmospheric removal

作者：Juan Miguel González-Sánchez, Nicolas Brun, Junteng Wu, Sylvain Ravier, Jean‐Louis Clément, Anne Monod · 发表于：Atmospheric chemistry and physics · 年份：2023 · DOI：10.5194/acp-23-5851-2023 · 被引用次数：17 · 研究领域：Atmospheric chemistry and aerosols、Atmospheric Ozone and Climate、Air Quality Monitoring and Forecasting

Organic nitrates (RONO 2 ) are secondary compounds, and their fate is related to the transport and removal of NO x in the atmosphere. While previous research studies have focused on the reactivity of these molecules in the gas phase, their reactivity in condensed phases remains poorly explored despite their ubiquitous presence in submicron aerosols. This work investigated for the first time the aqueous-phase photolysis-rate constants and quantum yields of four RONO 2 (isopropyl nitrate, isobutyl nitrate, α -nitrooxyacetone, and 1-nitrooxy-2-propanol). Our results showed much lower photolysis-rate constants for these RONO 2 in the aqueous phase than in the gas phase. From alkyl nitrates to polyfunctional RONO 2 , no significant increase of their aqueous-phase photolysis-rate constants was observed, even for RONO 2 with conjugated carbonyl groups, in contrast with the corresponding gas-phase photolysis reactions. Using these new results, extrapolated to other alkyl and polyfunctional RONO 2 , in combination with estimates for the other atmospheric sinks (hydrolysis, gas-phase photolysis, aqueous- and gas-phase ⚫OH oxidation, dry and wet deposition), multiphase atmospheric lifetimes were calculated for 45 atmospherically relevant RONO 2 along with the relative importance of each sink. Their lifetimes range from a few minutes to several hours depending on the RONO 2 chemical structure and its water solubility. In general, multiphase atmospheric lifetimes are lengthened when RONO ...