A hydrometallurgical process flowsheet for recovering MoO3 from Molybdenite

In this study, a comprehensive hydrometallurgical processing of molybdenite (MoS₂) concentrate was investigated. This investigation involved a novel approach combining mechanical activation, leaching, and polyelectrolyte extraction methods. The integrated method effectively addressed the challenge of low leaching rate of molybdenite, resulting in the successful production of high-purity molybdenum trioxide. Milled molybdenite samples were analyzed by different methods of X-ray diffraction, atomic force and electron microscopy, and BET. The increasing trend of the specific surface area during milling was determined by a model fitting which was useful for optimization of milling time. Several leaching reagents were studied to achieve high molybdenum dissolution. The most promising results were achieved through a two-hour process, yielding an impressive leaching efficiency of 80% and a resulting Mo concentration of 6700 mg/L. Molybdenum recovery was efficiently carried out through polyelectrolyte extraction, as confirmed by ICP and CHNS analyses, demonstrating selective precipitation of molybdenum from the solution. The subsequent calcination of the precipitated molybdenum(VI) compound resulted in the production of high-purity molybdenum trioxide. Furthermore, a conceptual hydrometallurgical treatment process for molybdenite concentrate was proposed, aiming to recover molybdenum, sulfuric acid, and copper. This proposed process presents a promising avenue for further exploration in pilot plant studies within the molybdenum industry.