Can gravity separation be used for molybdenum ore beneficiation?

Molybdenum ore is used as a chemical raw material to produce catalysts, lubricants, pigments, and fertilizers, and is a rare metal. Can gravity separation be used for molybdenum ore beneficiation? The main beneficiation method for molybdenum ore is flotation, and the recovered molybdenum mineral is molybdenite. Sometimes, to improve the quality of molybdenum concentrate and remove impurities, the concentrate undergoes further chemical beneficiation.

There are more than twenty known molybdenum minerals in nature. Among them, molybdenite has relatively large reserves and high industrial value. Currently, only molybdenite is recovered through beneficiation. Porphyry and skarn molybdenum deposits are the main molybdenum deposits in my country, each accounting for more than 40% of the total molybdenum reserves.

Molybdenite crystals have a hexagonal layered or platy structure, formed by S-MO-S structures along interlayer van der Waals bonds and intralayer polar covalent bonds S-Mo. The bonding force between layers is very weak, while the covalent bond force within layers is very strong. Therefore, molybdenite readily fractures along the interlayer structure, occurring in platy or flaky forms, which explains its naturally good floatability. Practice has shown that at appropriate grinding fineness, molybdenite crystal liberation occurs between the S-MO-S layers, with the hydrophilic S-Mo facets accounting for a very small proportion. However, over-grinding increases the proportion of the S-Mo facets, decreasing floatability. Although adding a certain amount of polar collectors such as xanthates can improve molybdenite recovery, the new slime generated by over-grinding affects flotation efficiency. Therefore, over-grinding must be avoided and prevented in molybdenite beneficiation. In production, staged grinding and multi-stage beneficiation processes are necessary to gradually achieve monomer liberation and ensure high molybdenum concentrate recovery.