Kinetics of bubble collision and attachment to hydrophobic solids: I. Effect of surface roughness

Meaningful Contact Angles in Flotation Systems: Critical Analysis and Recommendations

“…33 Nicely executed bubble attachment experiments demonstrated the bouncing of bubbles on the 'smooth' surface of a hydrophobic Teflon plate. 34 Similar gas bubbles attached spontaneously to a rough surface of the same polymer. The authors attributed the enhanced bubble attachment to the surface roughness, which enhanced the nucleation of micro-/nanobubbles in spaces between asperities.…”

“…It should be recognized that the repulsive electrical double-layer forces might also inhibit the bubble from attachment even to a very hydrophobic surface. 34 To eliminate this effect, a higher content of electrolyte is needed that drives compression of the electrical double layer and reduces the range of electrical double-layer forces.…”

Modification of ilmenite surface chemistry for enhancing surfactants adsorption and bubble attachment

“…Studies on froth flotation have been focused on developing techniques to selectively modify mineral surface chemistry to improve the hydrophobicity and the attachment of particles to air bubbles [8][9][10][11][12][13][14][15], and on investigating the effect of bubble sizes [16,17] and hydrodynamic interaction [18,19], etc. The typical opinion is that the poor ability is due to the reduced particle hydrophobicity and hence less probability of particle/air attachment [20,21].…”

Bubble impingement and the mechanisms of heat transfer

“…Several studies have reported experimental results concerning impingement and subsequent bouncing of a single gas/vapour or liquid bubble on a wall in various fluids [3][4][5][6][7][8][9][10][11][12][13][14]. Many of these authors investigated bubble impact against deformable surfaces, such as the interface between water and air, where coalescence would most likely occur [3,4,[6][7][8]10], while the remaining authors have investigated the effect of a bubble bouncing against solid surfaces [5,9,[12][13][14].…”

“…Krasowska & Malysa [11] studied the influence of surface roughness of hydrophilic and hydrophobic plates on the kinetics of the bubble attachment. They found that the roughness of the hydrophobic surface is of importance for the kinetics of the bubble attachment.…”