Oxidation Reactions of Sulfur and Nitrogen Compounds in the Atmospheric Aqueous Phase

Abstract

Oxidation reactions of atmospheric sulfur and nitrogen compounds dissolved in aqueous solutions are reviewed. Important viewpoints were summarized in a matrix-like form for evaluating chemical reactions in the aqueous systems. Recent progresses are addressed for kinetics and mechanisms of the oxidation of major chemical species such as SO₂, NO₂, and H₂S by H₂O₂, O₃, and free radicals. Much of the informationis potentially applicable as well as to lake and ocean surface waters which compose the interface of the atmosphere.
Among the conclusions are the following:(1) Rate laws and rate constants are established for S (IV)-0₃ and S (IV)-H₂O₂ systems.(2) Reactions with OH and SO₄^- radicals are shown to be very important.(3) Reliable mechanisms are presented for the Fe (III)-catalyzed autoxidation of S (IV).(5) Accommodation coefficients are precisely determined for SO₂, H₂O₂, and 0₃.