THE EFFECT OF PRETREATMENT ON MAGNETIC SEPARATION OF FERRUGINOUS MINERALS IN BAUXITE

This study investigates the effectiveness of various pretreatment techniques on the magnetic separation of ferruginous minerals from bauxite samples collected from Jamnagar, India, aimed at improving their suitability for refractory applications. The primary objective was to determine the optimal magnetic intensity required for effective separation of iron minerals. Methodologically, different magnetic separators and varying intensities were applied to various pretreated samples. The results of the study reveal that for crude bauxite, a magnetic intensity of 14,000 Gauss is necessary for effective removal of ferruginous minerals. In contrast, when the bauxite sample was calcined at 800°C, a lower magnetic intensity of approximately 7,000 Gauss sufficed, while reduced bauxite required less than 2,000 Gauss for effective iron separation. Post-separation analysis of the products showed that the treated bauxite achieved an alumina content of 76%, with both 62% iron removal and a recovery of 69% alumina. These outcomes indicate that the treated bauxite products meet the criteria for refractory utilization, underscoring the potential of magnetic separation as a viable beneficiation method for low-grade bauxite ores.