| The hydrophobic flocculation of fine molybdenite particles as function of various emulsion methods of kerosene, dosage and concentration of oil emulsion and pH were investigated wholly by flotation, as well as speed and duration of stirring. The emulsion degree of kerosene and flocculation behavior of fine molybdenite particles were also studied by optical microscope, SEM and Zeta potential measurements.The flotation results show that hydrophobic floc-flotation respond could be greatly increased by adding kerosene and giving to mechanical stirring. The higher the emulsion degree of kerosene, the stronger the hydrophobic flocculation is. Besides, the optimal condition of flotation is at the range of pH 5.5~6.5, on the contrary, the flotation respond falls substantially in alkaline condition.The results of microscope show that the size of fine molybdenite particles as a hydrophobic aggregation is obviously larger than original size and the aggregation structure is irregular and compact. In addition, the absolute value of Zeta potential increases greatly with decreasing the particle size of molybdenite, as well as the increase of the edge/face ratio. According to DLVO theory, the electric double layer repulsion between particles arisen from particle surface charges is mainly determined byζpotential. Hence, the energy barrier should be increased due to the increase of the negativeζpotential, leading to prevent aggregation of fine particles. It is expected that the finer the particle sizes of molybdenite and the higher the edge/face ratio, the lower the flotation respond.
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