Effect of inevitable ions on kerosene droplet formation and evolution

BACKGROUND: Understanding the effect of ions on collector generation characteristics is crucial for adjusting the oil/water interface and enhancing mineral flotation.METHODS: We conducted a study of the kerosene droplet generation process in the presence of NaCl, MgCl2, and AlCl3 using a high-speed motion acquisition system.RESULTS AND CONCLUSIONS: The results showed that the generation process of kerosene droplets could be divided into two stages, droplet expansion and column contraction, according to variations of the droplet width. With the increasing capillary inner diameter, the generation time of the kerosene droplet increased, while the w/h value (column width/column height) of the kerosene column decreased. When the w/h value decreased to 0, the droplet column ruptured, and the droplet separated from the capillary. As the ion valence increased, the equivalent diameter (d) of the kerosene droplet increased due to the ionic hydration and followed the order d(Al)(3+) > d(Mg)(2+) > d(Na)(+). Furthermore, as the ion concentration increased, the equivalent diameter increased with the same capillary inner diameter, and the w/h value decreased. A model of the kerosene column height and capillary inner diameter (R) was established to predict the characteristics of the generated kerosene droplet.(c) 2023 Society of Chemical Industry (SCI).