Enhanced fine flake graphite flotation and reduced carbon emission by a novel water-in-oil kerosene emulsion

Kerosene is a frequently-used collector in graphite flotation; however, its consumption substantially increases due to its poor dispersibility in water and the depletion of graphite resources. We prepared a novel water-in-oil type kerosene emulsion as a more efficient collector for graphite flotation. The effect of preparation parameters on the emulsion stability was investigated by particle size analysis, stratification test, and electrical conductivity test. The results indicated that particle size played a dominant role in the stability of emulsified kerosene. The smaller emulsified kerosene droplets contribute to a more stable emulsion dispersion. Optical microscope and Cryo-SEM techniques visualized a stable and homogenous emulsion with an average particle size of 1–2 µm. Furthermore, batch flotation and adsorption tests indicated that the emulsified kerosene outperformed pristine kerosene as a collector in fine flake graphite flotation, increasing the flotation recovery by approximately 3%, with 26%− 34% kerosene consumption reduction. Our study provides a valuable pathway for developing emulsified collectors for clean flotation of graphite ores, especially for reducing carbon emission. [Display omitted] •A water-in-oil kerosene emulsion was prepared using Span-80 as the emulsifier.•Emulsified kerosene outperformed pristine kerosene as a collector in fine flake graphite flotation.•Kerosene emulsion increased the graphite recovery by 3% with 26%− 34% reduced kerosene consumption.•Cryo-SEM was employed to visualize the in-situ microstructure of the emulsion.