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Title: The dynamics of rising oil-coated bubbles: experiments and simulations
Air bubbles rising through an aqueous medium have been studied extensively and are routinely used for the separation of particulates via froth flotation, a key step in many industrial processes. Oil-coated bubbles can be more effective for separating hydrophilic particles with low affinity for the air–water interface, but the rise dynamics of oil-coated bubbles has not yet been explored. In the present work, we report the first systematic study of the shape and rise trajectory of bubbles engulfed in a layer of oil. Results from direct observation of the coated bubbles with a high-speed camera are compared to computer simulations and confirm a pronounced effect of the oil coat on the bubble dynamics. We consistently find that the oil-coated bubbles display a more spherical shape and straighter trajectory, yet slower rise than uncoated bubbles of comparable size. These characteristics may provide practical benefits for flotation separations with oil-coated bubbles.  more » « less
Award ID(s):
1706475
PAR ID:
10058132
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Soft Matter
Volume:
14
Issue:
14
ISSN:
1744-683X
Page Range / eLocation ID:
2724 to 2734
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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