The efficient flotation of molybdenite fines based on the synergistic regulation of anisotropic interface using a novel compound collector

The composite collector surpassed single collector on molybdenite fines flotation. • PEG600MO chemisorbed on edge and promoted the adsorption of emulsified kerosene. • PEG600MO and emulsified kerosene co-adsorbed on face to enhance its hydrophobicity. • The synchronous interfacial regulation was realized using the composite collector. The efficient recovery of fine molybdenite particles remains a significant challenge in mineral processing, largely attributed to the remarkably enhanced hydrophilicity as particle size reduces. Conventional non-polar collectors show limited effectiveness in floating such fine fractions. In the present study, a novel composite collector made of poly ethylene glycol 600 monooleate (PEG600MO) and emulsified kerosene was designed to boost the flotation of molybdenite particles smaller than 20 μm, relying on the synchronous interfacial modulation of both faces and edges. Flotation test results indicated that this composite collector outperformed individual collectors, significantly improving the flotation efficiency of fine molybdenite particles. The results of contact angle, electrokinetic measurements, Fourier transform infrared spectroscopy (FTIR), adsorption capacity and electrochemical tests demonstrated that PEG600MO was inclined to adsorb on molybdenite edges, promoting emulsified kerosene to adsorb on edges through hydrophobic interactions, meanwhile PEG600MO and emulsified kerosene co-adsorbed on faces physically. The differential adsorption of various components significantly improved the hydrophobicity of both faces and edges. X-ray photoelectron spectroscopy (XPS) results confirmed that the hydroxyl groups in PEG600MO underwent chemical interactions with Mo atoms on molybdenite. This work developed an effective composite collector and offered a new perspective on the design of flotation reagents for the efficient recovery of fine molybdenite particles.