Roles and Influences of Kerosene on Chalcopyrite Flotation in MgCl2 Solution: EDLVO and DFT Approaches

Seawater has been increasingly used as an alternative to freshwater in mineral flotation. Although previous studies suggest that Mg2+ ions in seawater have the primary negative roles in chalcopyrite flotation, insufficient work has been conducted to understand the effects of kerosene as a collector in chalcopyrite flotation. In this study, the influence of kerosene emulsion on chalcopyrite floatability in a solution containing Mg2+ was systematically investigated. The results indicated that the addition of kerosene significantly reduced the adsorption of hydrophilic Mg-precipitates onto the chalcopyrite’s surface. In addition to contact angle, zeta potential, optical microscopy, and Fourier-transform infrared spectroscopy analyses, extended Derjguin–Landau–Verwey–Overbeek (EDLVO) theory and density functional theory (DFT) calculations were conducted to understand the influencing mechanisms of kerosene on chalcopyrite flotation. The adsorption energies showed an order of kerosene and Mg(OH)2 > kerosene and chalcopyrite > chalcopyrite and Mg(OH)2, indicating kerosene was preferentially adsorbed on the Mg(OH)2 surface, forming agglomerates and therefore reducing the adsorption of Mg(OH)2 precipitates onto the chalcopyrite’s surface. In addition, hydrophobic agglomerates were also formed due to the attachment of kerosene to the chalcopyrite’s surface when additional kerosene was added, further enhancing chalcopyrite floatability.

Influence Mechanism of Magnetized Modified Kerosene on Flotation Behavior of Molybdenite

The effects and mechanism of magnetized kerosene on the flotation behaviors of molybdenite were studied by micro-flotation, ultraviolet spectrum, infrared spectrum, surface tension, and liquid viscosity. According to the results of micro-flotation, magnetized kerosene improved the flotation recovery of molybdenite, and the improvements were more obvious with smaller molybdenite particles. Spectral analysis showed that the magnetization did not change the chemical composition of kerosene, but transformed the linear aliphatic hydrocarbons in kerosene into linear isomers and reduced the lengths of the carbon chains. Moreover, the magnetization reduced the viscosity of kerosene and oil/water interfacial tension, and improved the dispersion of kerosene in the pulp. The external magnetic field transformed the disorder of the additional magnetic moment in the kerosene molecules into order, and reduced the compactness of the kerosene molecules. The experimental results provided a theoretical explanation for the role of magnetization in mineral flotation.

Improvement of reagent flotation modes of sphalerite and pyrite from deposits of copper-zinc pyrite, polymetallic copper-zinc pyrite and polymetallic ores

Copper-zinc pyrite (Sulphide) and polymetallic ores of Russia are complex and difficult to process mineral raw materials. The main technology for the enrichment of this ores are flotation. Currently, the improvement of the flotation technology of this mineral raw materials is carried out in several way. It has been established by the practice of beneficiation of copper-zinc ores that obtaining high-quality zinc and pyrite concentrates is impossible without adding flotation modifiers of sphalerite and pyrite to various flotation operations. This reagent are copper (II) sulfates, zinc and iron (II) sulfates in an alkaline calcareous medium. Therefore, studies on the flotation of sphalerite and pyrite in an alkaline calcareous medium with the addition of one of these metal sulfates to the mineral flotation operation were performed. The effect of each copper (II) sulfates zinc, and iron (II) on the flotability of sphalerite and pyrite was studied during flotation of the mineral and xanthate and dithiophosphate at pH = 8, 10, and 12. The aim of this work was to study the effect of the flotation size class (- 0.074 + 0.044 mm) sphalerite and pyrite of one of the Russian deposits by sulfhydryl collectors in the presence of copper, zinc and iron sulfates in the liquid phase of flotation pulp

Selection of an Appropriate Depressant in Flotation Separation of Molybdenum Oxide from Fluorapatite

The depressive efficiency of sodium silicate, sodium hexametaphosphate, and tartaric acid on the flotation separation of molybdenum oxide from fluorapatite were examined using cetylpyridinium chloride (CPC) as the collector. The corresponding depression mechanisms of all three depressants were studied with the use of laboratory measurements. Individual mineral flotation tests and adsorption studies showed that all these depressants have a higher depression effect on fluorapatite than molybdenum oxide. Sodium hexametaphosphate has the strongest depression effect on fluorapatite and can reduce the flotation recovery as low as less than 20%. Infrared spectroscopy and zeta potential tests proved the rationality of the flotation results, indicating that when CPC was used as a collector, the effect of sodium hexametaphosphate on the surface of molybdenum oxide was smaller than that on fluorapatite. The adsorption of hexametaphosphate on the surface of fluorapatite was determined to be physical adsorption.