Recent advances for understanding the role of nanobubbles in particles flotation

From Microbubbles to Nanobubbles: Effect on Flotation

“…The flotation performance (both recovery and kinetics) of ultrafine coal particles was said to be remarkably improved in the presence of nanobubbles; particle aggregates induced by nanobubble bridging has been recognized as one of the main contributors to improve the flotation performance of minerals [60]. It is generally believed that bubble miniaturization should be of significance to improve flotation efficiency [61]. Zhang et al investigated the development of a new method that introduces interfacial nanobubbles (INBs) based on the temperature difference method for enhancing lignite flotation.…”

“…In the presence of INBs, the induction time of lignite can be reduced from 400 ms to 27.21 ms, the number of bubble-particle collisions from 4 to 3, and the attachment time from 208 ms to 128 ms. When a macroscopic air bubble approaches a lignite surface with INBs, the air bubble first merges with the INBs, not only decreasing the induction time but also increasing the apparent contact angle and length of three-phase contact line [61].…”

Does salting-out effect nucleate nanobubbles in water: Spontaneous nucleation?

“…Bulk nanobubbles possess distinct features such as extraordinary longevity, high surface to volume ratio , high mass transfer coefficient and Laplace pressure, ability to generate reactive oxygen species. Owing to such peculiar properties, nanobubbles have wide range of applications in the field of wastewater treatment [1] , [2] , medical application [3] , food processing [4] , environmental sectors [5] , bio-engineering sectors [6] , flotation [7] , therapeutic delivery [8] . Despite such overwhelming applications, the fundamental understanding of nanobubble generation [9] and a unique characterization technique to distinguish nanobubbles from the particle and nanodroplet [10] are still under infancy.…”

Effect of the ultrasonic standing wave frequency on the attractive mineralization for fine coal particle flotation

“…), technologies (nanobubble assisted flotation, fluidized bed, etc. ), and flotation chemicals (reagents) have been considered to enhance the inertial effect between particles and bubbles (bubble mineralization) and to improve the collision efficiency of fine particles [3] , [4] , [5] , [6] , [7] .…”