Extraction of Iron and Alumina from Red Mud with a Non-Harmful Magnetization Sintering Process

Red mud, which could cause numerous problems to the environment, is a hazardous waste generated from alumina smelting industry. In general, storage and harmless utilization of red mud are hard implement due its fine particle size high alkalinity. This study put forward novel process separate iron (MgFe2O4) (Al2O3) in by magnetization sintering method. The magnesium oxide was added transform nonmagnetic Fe2O3 into magnetic MgFe2O4 achieve physical separation iron-bearing minerals, alumina-bearing minerals were converted dissoluble NaAlO2 one-step reaction. atmospheric pressure leaching adopted this for resource recovery. To clean production, silicate solution removed adding slightly soluble CaSO4, entire becomes harmless. feasibility verified thermodynamic analysis, series experiments performed detect optimum MgO/(Fe2O3 + MgO) ratio calcining conditions. morphological mineralogical characteristics modified product studied X-ray diffraction analysis (XRD) scanning electron microscopy (SEM) energy dispersive spectroscopy (EDS). It observed that under optimal conditions with 14.89% recover aluminum, corresponding recovery rates 67.54% 73.01% respectively, grade 30.46%. EDS results showed obtained Mg/Fe 0.4677–0.528, different standard at 0.5. new method can promote development comprehensive production.