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Coalescence of bubbles covered by particles
1Centre for Multiphase Processes, University of Newcastle, New South Wales, 2308, Australia. Seher.Ata@newcastle.edu.au
Langmuir : the ACS Journal of Surfaces and Colloids
|May 20, 2008
Summary
Glass particle-coated bubbles interacting with a cationic surfactant show increased coalescence time with higher surface coverage. Particles resist film drainage through capillary interactions, affecting bubble coalescence dynamics.
Area of Science:
- Colloid and Surface Science
- Fluid Dynamics
- Materials Science
Background:
- Bubble-particle interactions are crucial in various industrial processes.
- Cationic surfactants like cetyltrimethylammonium bromide (CTAB) influence interfacial properties.
- Understanding particle effects on bubble coalescence is key for process optimization.
Purpose of the Study:
- To experimentally investigate the coalescence of two bubbles coated with glass particles.
- To determine the effect of particle fractional coverage on coalescence time.
- To elucidate the role of particles in film drainage and rupture dynamics.
Main Methods:
- Experimental study of bubble-bubble interactions.
- Measurement of coalescence time as a function of particle surface coverage.
- Analysis of film drainage and rupture mechanisms in the presence of particles.
Main Results:
- Coalescence time increases with increasing fractional coverage of bubble surfaces by glass particles.
- Particles impede film drainage even at low surface coverage due to lateral capillary interactions.
- The presence of attached particles significantly affects bubble coalescence dynamics.
Conclusions:
- Particle coverage is a critical factor controlling bubble coalescence time.
- Lateral capillary interactions between particles play a significant role in resisting film drainage.
- The findings provide insights into the behavior of particle-laden foams and emulsions.
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