Effect of surfactant on the attachment between coal particles and bubbles: An experimental and molecular dynamics simulation study

Surfactant plays a vital role in flotation, especially in the adsorption of particle and bubble surface. From macroscopic to atomic scales, the effects of surfactant on the attachment between coal particles and bubbles were investigated by the induction time measurements, bubble-particle wrap angle measurements, thin liquid films measurements and molecular dynamics (MD) simulation. The three surfactants are Cetyltrimethylammonium bromide (CTAB), Sodium dodecylbenzene sulfonate (SDBS), and Methyl isobutyl carbinol (MIBC). Macroscopically, the coal particles could be more easily attached to a bubble surface in three solutions, particularly in CTAB solution. This was because the speed of thinning and rupture of thin liquid film between coal-particles and bubbles was faster in CTAB solution than that in other solutions. MD simulation findings show that the adsorption of CTAB significantly improves the water molecule migration rate. In addition, the CTAB promotes the attachment efficiency in floatation.