Recovery of Mo from Ni–Mo ore leach solution with carrier co-precipitation method

In this paper, “nascent” Fe(OH)3 as carrier precipitation and NaHCO3 as buffer agent were used to extract molybdenum from the complex Ni–Mo ore leach solution. The effects of different variables on the molybdenum extraction, such as the dosage of FeCl3 and NaHCO3 and the reaction temperature and time, were studied. The results showed that over 99% of molybdenum were extracted in 2 h at 25 ± 1 °C under the conditions of mole ratio of Fe3+/Mo 2.2–2.5 and mass ratio of NaHCO3/Mo 0.7–1.5. About 92% of Mo in the Fe(OH)3 precipitation can be leached by NH3⋅H2O to prepare the ammonium molybdate solution with about 100 g/L Mo. After treating with NH3⋅H2O, the Fe(OH)3 precipitation was dissolved with HCl to obtain the FeCl3 solution (FeCl3 500 g/L) which can be reused for the next round of experiments.

► Nascent Fe(OH)3 as carrier precipitation and NaHCO3 as buffer agent can be used to extract Mo from Ni–Mo ore leach solution.
► The extraction ratio of Mo was high; above 99% of Mo was extracted under the optimal conditions.
► The Fe(OH)3 precipitation can be reused for a new round of experiments, which decreases the cost.
► This method is easy to implement in industrialization because of its low cost, easy operation, large capacity and high efficiency.