Experimental Study on Aqueous Oxidation of Sulfur Dioxide by Ozone under the Presence of Mn2+

The aqueous removal of sulfur dioxide (SO₂) by oxidation of Mn²⁺ catalytic ozone was investigated in the experiments, so as to find the effects of Mn²⁺ for aqueous removal of SO₂ by ozone. The concentration curve of ozone was measured by standard iodine measurement method. The operating factors included mole ratio of ozone to SO₂ and the concentrations of Mn²⁺. When absorption solution has no Mn²⁺, the removal efficiency of SO₂ is 35% at 0.5 mole ratio of O₃ to SO₂, but the efficiency is 70% when Mn²⁺ is put into absorption solution at the same mole ratio of O₃ to SO₂. As it is increasing, the removal efficiency of SO₂ increases. And as concentration of Mn²⁺ increases, the efficiency also increases. At the end of the experimental studies, we made the conclusion that the optimal concentration range of Mn²⁺ for the aqueous removal of SO₂ by Mn2+ catalytic ozone is 1.2×10^-2~1.2×10^-1 mol/L.