Atmospheric oxidation of sulfur dioxide (SO₂) forms sulfate-containing aerosol particles that impact air quality, climate, and human and ecosystem health. Multiphase oxidation of SO₂ in aerosol particles plays an important but poorly understood role in forming sulfate aerosols. This is highlighted by the fast sulfate formation in cloud-free yet highly polluted urban environments. In this talk, I will present the results of laboratory experiments to directly measure the rates of sulfate formation from multiphase oxidation of SO₂ by H₂O₂, transition metal ions, and NO₂ in aerosol particles. The atmospheric importance of the above aerosol multiphase SO₂ oxidation pathways will be discussed.

Sulfate,Multiphase Chemistry,flow tube,smog chamber