Leaching of Neodymium From Hard Disk Drive Magnet Waste Using Citric Acid‐ Design of Experiments and Optimization

Abstract Neodymium magnet waste recycling and precious metal recovery have drawn a lot of researchers’ attention because of their vital role in contemporary technology. In this work, the potential of citric acid for the leaching of neodymium from hard disk drive waste magnets has been examined using statistical approaches like full factorial design(FFD) and central composite design (CCD).The variables have been screened and conditions are optimized to obtain higher leaching. The polynomial quadratic Model proves effective to predict optimized conditions for neodymium leaching. Leachant concentration and temperature were screened as the most effective factors. Optimization conditions for the leaching process were achieved through central composite design, revealing that 2 mol/L citric acid and a temperature of 333 K provide the ideal conditions for the complete dissolution of neodymium. This extensive study contributes to sustainable materials management and resource conservation by illuminating the effective recovery of important metals from neodymium magnets.