THE HETEROGENEOUS OXIDATION OF SO2 ON AEROSOL SURFACE

A heterogeneous chemical model is developed by coupling aerosol, gas-p hase and liquid-phase chemical model. SO2 oxidation rates on the aeros ol surface are calculated and the influence of some factors is discuss ed. Model simulations indicate that SO2 heterogeneous oxidation rates are sensitive to the mass concentration and chemical composition oi ae rosols, relative humidity, initial values oi SO2 and H2O2. The heterog eneous chemical model is coupled with a Eulerian deposition model. Mod el results show that oxidation of SO2 on the aerosol surface is found to reduce SO2 levels by 5%-33%, to increase SO42- concentrations by 8% -50% in the surface layer.