A Study on Recovery of Iron from Red Mud by Solid State Reduction Followed by Magnetic Separation

Abstract

Red mud is a waste material of the Bayer process for alumina production from bauxite ore. Red mud is generally pumped to disposal in an artificial pond which is accompanied by great land occupation and environmental issues. Many researches in different fields have been carried out to evaluate the red mud. Of these, researches on recovering valuable metals from red mud are the most successful. In this study, recovery of iron, which is the most abundant metal in red mud, was investigated. A red mud sample with 34% Fe2O3 was used. Solid state carbothermic reduction followed by wet magnetic separation was performed to recover iron. Reduction was carried out at temperatures 1000–1200 °C. Reduced samples were ground and subjected to wet magnetic separation. The effect of reduction temperature and grinding time were investigated on the metallization of iron and the iron content of the final concentrate.