Study on the Removal of Arsenic in Pyrite Cinder by Acid Leaching

For effectiveutilization of sulfate slag, the content of iron (Fe) should higher than 60%, while the content of asenic (As) should lower than 0.05%. A sulfate slagpretreated by magnetic separation-gravity separation, contains Fe 58.61% and As 0.33%, and the forms of Fe and As are mainly Fe2O3 and FeAsO4. To obtain qualified Fe ore concentrateproduct, chemical leaching conditions was used to remove As. Results show that the the optimal conditions are -0.074mm 75%grinding fineness, 30 degrees C,15 g/L initial acid, 5/1 liquid-solid ratio,350 rpm mixing intensity and 60 min leaching time. The obtained qualified product contains Fe 61.85%, As 0.045%, and Fe recovery rateis 98.63%.