Study on Sulfur Dioxide Decomposition over Oxygen-deficient Ferrite

The oxygen-deficient ferrite (Fe₃O_4-¿) was prepared by reduction of the natural magnetite powder with CO, and the performance of the Fe₃O_4-¿ in decomposing SO₂ into elemental sulfur was investigated. The samples, prepared by wet ball-milling of the magnetite using water as solvent for 500 hours, were characterized by means of SEM and XRD, and their activity of decomposing SO₂ was tested by measuring pressure variation of the reaction system. The results showed that the activity of SO₂ decomposition over the sample appeared as a principle of single peak rule with the different reduction conditions. The Fe₃O_4-¿, prepared under the reduction conditions of temperature 673 K, CO flux 40 mL/min and reducing time 6 hours, achieved the best SO₂ decomposing rate of 1.414×10-3 mole per gram of catalyst. Some FeS₂ was also formed in the decomposition process.