Decomposition of SO2 with CO reduced magnetite: Effect of CO flow rate

This work investigated the decomposition efficiency of SO₂ with oxygen-deficient magnetite. The natural magnetite was grinded with wet ball-milling method to prepare sub-micrometer size magnetite powder. The powder was characterized by SEM and XRD. Oxygen-deficient Ferrite Fe₃O_4-δ was reduced from natural magnetite in the CO gas flow. The activity of decomposing SO₂ with Fe₃O_4-δ was tested by measuring the pressure variation of the SO₂ system. The results showed that the activity of decomposing SO₂ by oxygen-deficient magnetite appeared as a single peak in the range of input CO flow rate. Under the experimental parameters: the temperature of 673K, CO flow rate of 40ml/min and the reducing time of 6 hours, the CO reduced magnetite showed the best efficiency of decomposing SO₂, that is, 1.414 × 10^-3 mol (SO₂)/g (Fe₃O_4-δ). New material (FeS₂) appeared in the Fe₃O_4-δ powder during the decomposition process.