Indexed on: 06 Jul '16Published on: 04 Jul '16Published in: Colloids and Surfaces A: Physicochemical and Engineering Aspects
Flotation and single bubble tests were performed to compare the kinetics of flotation and time of a bubble attachment to naturally hydrophobic solids with different degree of hydrophobicity that is highly hydrophobic polytetrafluoroethylene, moderate hydrophobic fluorite and slightly hydrophobic quartz. The paper identifies an important relationship between the flotation kinetics, expressed as the inversed first order rate constant (1/k), and time of three-phase contact formation (tTPC) determined from the single bubble tests. It was shown that flotation kinetics is mainly determined by the time of three-phase contact formation, that is the time from the first bubble collision to its attachment to the solid surface. Despite the complexity of flotation process, which includes vast number of sub-processes, the kinetics of drainage of liquid film separating the bubble and solid surfaces seems to be a factor of crucial importance for the final flotation outcome.