International Mineral Processing Symposium, Eskişehir, Türkiye, 16 - 18 Ekim 2024, ss.423-432
This study investigates the rheological behavior of acid-leached sepiolite, focusing on improving its properties through mechanical activation and nitric acid treatment. Sepiolite from the Türktaciri region of Sivrihisar was mechanically activated using a rotor-stator homogenizer to disperse the fiber bundles. The activated sepiolite was then subjected to nitric acid leaching to remove dolomite impurities. The effects of varying acid concentrations on sepiolite enrichment were examined using X-ray fluorescence (XRF) and X-ray diffraction (XRD) analyses. Results showed that the sepiolite content could be increased from 84.4% to 91.9% using a nitric acid molar ratio sufficient to dissolve 80% of the dolomite present. However, exceeding this ratio led to a rapid decrease in sepiolite content. The study found that at a 40% molar ratio, the sepiolite grade increased to 88% with 92% enrichment efficiency, while at an 80% molar ratio, the sepiolite grade reached 92% with 82% enrichment efficiency. These findings provide insights into optimizing the acid leaching process for enhancing sepiolite's rheological properties, which is crucial for its industrial applications.