Oxidative acid leaching behavior of Fe-Ni-Co alloy powder derived from a laterite ore

The demand for Ni and Co has surged due to the rapid expansion of the electric vehicle industry. Thus, developing efficient and eco-friendly metallurgical routes for extracting these metals has become imperative. This study introduces a sustainable and effective method for extracting Ni and Co from Ni-Co-Fe alloy powder obtained from limonitic laterite ores through selective reduction and magnetic separation. The leaching efficiency for Ni, Co, and Fe was 89.4%, 94.8%, and 96.5%, respectively, under the following conditions for leaching: 3 mol/L H2SO4, 85 degrees C, 10 mL/g liquid-solid ratio, and 90 min leaching time. The incorporation of H2O2 enhanced the leaching efficiency for Ni, Co, and Fe. The redox potential of the solution plays a crucial role in acid dissolution, and H2O2 enhances Ni and Co dissolution. Phosphate precipitation facilitated the removal of Fe from the leachate, affording a 96.1% Fe removal ratio and 2.29% Ni loss.