Leaching of Indium from Zinc Indium Ferrite under the Synergistic Enhancement of Microwave and Mechanical Activation

In response to the problem of low indium leaching efficiency in conventional acid leaching processes, a method of the mechanical activation and microwave synergistic enhancement was adopted to extract indium from zinc indium ferrite through acid leaching. The lattice structure changes of zinc indium ferrite before and after mechanical activation were analyzed, and the influence of different process factors on the leaching behavior of indium from zinc indium ferrite was studied. The kinetics of indium leaching process under mechanical activation and microwave synergistic enhancement was also analyzed. The results show that after mechanical activation, the crystal structure of zinc indium ferrite is destroyed, the diffraction peak intensity decreases, the peak pattern widens, the grain size decreases, and the lattice strain increases. Under the conventional conditions, the highest indium leaching rate is only 59.2% at the low temperature and low aci, and 92.0% at the high temperature and acid (150 min). When microwave and mechanical activation act separately and synergistically, the promotion of indium leaching rate at low temperature and low acid is not significant, while the leaching rate under high temperature and high acid conditions reaches 100%, and the time gradually decreases to 120, 90, and 60 min, respectively. The synergistic effect of mechanical activation and microwave significantly improves the efficiency of indium leaching. The surface chemical reaction control model is suitable for the kinetic process of indium leaching under the synergistic effect of mechanical activation and microwave.