Mass transfer between microbubbles

Yuqi Yang; Matthew D Biviano; Jixiang Guo; Joseph D Berry; Raymond R Dagastine

doi:10.1016/j.jcis.2020.02.120

Mass transfer between microbubbles

J Colloid Interface Sci. 2020 Jul 1:571:253-259. doi: 10.1016/j.jcis.2020.02.120. Epub 2020 Mar 2.

Authors

Yuqi Yang¹, Matthew D Biviano², Jixiang Guo³, Joseph D Berry⁴, Raymond R Dagastine⁵

Affiliations

¹ State Key Laboratory of Heavy Oil Processing at Karamay, China University of Petroleum-Beijing at Karamay, Karamay 834000, China; Institute of Unconventional Oil and Gas Science and Technology, China University of Petroleum, Beijing 102249, China.
² Department of Chemical Engineering, University of Melbourne, Parkville 3010, Australia.
³ Institute of Unconventional Oil and Gas Science and Technology, China University of Petroleum, Beijing 102249, China.
⁴ Department of Chemical Engineering, University of Melbourne, Parkville 3010, Australia. Electronic address: berryj@unimelb.edu.au.
⁵ Department of Chemical Engineering, University of Melbourne, Parkville 3010, Australia. Electronic address: rrd@unimelb.edu.au.

PMID: 32203761
DOI: 10.1016/j.jcis.2020.02.120

Abstract

Hypothesis: The role of interfacial coatings in gas transport dynamics in foam coarsening is often difficult to quantify. The complexity of foam coarsening measurements or gas transport measurements between bubbles requires assumptions about the liquid thin film thickness profile in order to explore the effects of interfacial coatings on gas transport. It should be possible to independently quantify the effects from changes in film thickness and interfacial permeability by using both atomic force microscopy and optical microscopy to obtain time snapshots of this dynamic process. Further, it is expected that the surfactant and polymer interfacial coatings will affect the mass transfer differently.

Experiments: We measure the mass transfer between the same nitrogen microbubbles pairs in an aqueous solution using two methods simultaneously. First, we quantify the bubble volume changes with time via microscopy and second, we use Atomic Force Microscopy to measure the film thickness and mass transfer resistances using a model for the gas transport.

Findings: Modelling of the interface deformation, surface forces and mass transfer across the thin film agrees with independent measurements of changes in bubble size. We demonstrate that an anionic surfactant does not provide a barrier to mass transfer, but does enhance mass transfer above the critical micelle concentration. In contrast, a polymer monolayer at the interface does restrict mass transfer.

Keywords: Atomic force microscopy; Bubbles; Colloids; Interfaces; Mass transfer; Ostwald ripening; Soft matter; Thin films.