Separation of Molybdenite and Talc by Seawater Flotation: Research on the Treatment Method and Mechanism of Galvanic Corrosion–Seawater Immersion

The molybdenite and talc flotation separation process requires a lot of fresh water resources, but fresh water resources are scarce; the use of seawater instead of fresh water for flotation has received increasing attention. This paper studied the influence of galvanic corrosion-seawater immersion treatment on the flotation behavior of molybdenite in seawater medium under different galvanic corrosion-seawater immersion treatment conditions (including seawater immersion treatment time, solid-liquid ratio of seawater immersion, galvanic corrosion time, and galvanic corrosion ambient temperature). A method for enhancing the flotation separation of molybdenite and talc in seawater medium by galvanic corrosion-seawater immersion treatment was established for the first time. Furthermore, the differences in the effects of galvanic corrosion-seawater immersion treatment on the surface properties of molybdenite and talc were studied by using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy, and energy-dispersive spectroscopy (SEM-EDS) and contact angle testing techniques. The results of the flotation test show that the galvanic corrosion-seawater immersion treatment can significantly expand the floatability difference between molybdenite and talc. The results of the artificial mixed ore flotation test show that 96.29% of the molybdenite was suppressed in the tailings (molybdenite products) after the galvanic corrosion-seawater immersion treatment. This indicates that the galvanic corrosion-seawater immersion treatment can effectively inhibit the flotation recovery of molybdenite in the mixed ore in the seawater medium. The research results can promote the development of molybdenite seawater flotation separation technology, expand the application scope of seawater flotation technology in the field of mineral processing, and contribute to the green and sustainable development of the mining industry.