On a New Mode of Catalytic Sulfite Oxidation in the Presence of Mn(II) and Excess Metal Ions

Data on the kinetics of sulfite oxidation catalyzed by manganese(II) ions in the presence of excess metal ions have been discussed. Information on the dynamics of the reaction in aerosol particles, along with results of tests in solutions, has been involved. A fast degenerate-branched (DB) reaction mode has been first revealed. The dynamics of the mode is determined by the rate of chain branching involving an inter-HSO-(5) mediate and Mn(II) ions. Estimates of the rate constant of this reaction have been described; a criterion for the transition of the reaction into the DB mode has been discussed. It has been shown that the apparent accel-eration of sulfate formation in the DB mode in tests with aerosols is the result of the coupling of the catalytic reaction and the capture of SO2 from the gas. Calculations in terms of the reaction dynamics agree with the data of smog chamber tests and the atmospheric aerosol monitoring results.