Collaborative Research: Sulfur Oxide Chemistry in Aqueous Aerosols--Mechanisms and Kinetics of Inorganic Sulfate and Organosulfur Compound Formation in the Atmosphere

In this collaborative project, the research team will conduct laboratory experiments and box model simulations to study sulfur compound formation within aerosols. There currently exist gaps in the chemical representation of sulfate aerosol formation in models, especially during haze episodes, due to a lack of experimental data over a range of environmental conditions. This research team seeks to fill this gap. The knowledge gained could be used in large-scale atmospheric chemistry models, which has the potential to positively impact air quality management and climate change research communities. Additionally, three graduate students will be trained during this project, and bilingual (English and Spanish) outreach kits and videos will be developed and shared with non-technical audiences via new and ongoing outreach activities.The research, which represents a change to the conceptualization of sulfur dioxide atmospheric chemistry, aims to characterize the kinetics and chemical mechanisms for low- to high-oxidation state sulfur conversion pathways within multiphase and aqueous aerosols. The project includes three specific investigations: (1) the investigation of sulfate formation in aqueous aerosols via hydrogen peroxide, organic peroxides, and transition metal ion oxidation pathways under a range of pH and ionic strength conditions using an aerosol optical tweezer-based approach; (2) an investigation of the competition between sulfate and organosulfur formation via sulfate radical initiated formation pathways in aqueous aerosols under different pH, temperature, and ionic strength conditions; and (3) an investigation of sulfur dioxide chemistry within multiphase aqueous droplets that contain reactive metal-containing inclusions such as minerals and coal fly ash particles.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.