Combined Effects of Nanoparticles and Surfactants upon Foam Stability

Mohammad Javad Shojaei (1) , Yves Méheust (2) , Abdulkadir Osman (3) , Paul Grassia (4) , Nima Shokri (5)

1 Department of Earth Science and Engineering [Imperial College London]
2 GR - Géosciences Rennes
3 University of Manchester [Manchester]
4 University of Strathclyde [Glasgow]
5 TUHH - Hamburg University of Technology

We investigate effects of surfactants with different charges (anionic, cationic, and non-ionic) on foam stability in the presence of charge-stabilized silica (SiO2) nanoparticles. Toward this aim, a comprehensive series of experiments on a Hele-Shaw cell and a foam column is conducted at bubble and bulk-scale respectively, that is, investigating phenomenologies of foam coarsening separately by gas diffusion and bubble coalescence, and by gravitational drainage. Our results show nanoparticles, despite their ability to position themselves at liquid-gas interfaces and thus limit the resulting surface tension coefficient, do not necessarily have a positive effect on foam stability; the nature and magnitude of this effect depends strongly on the nature of the surfactant, its concentration and the concentration of nanoparticles. In less stable systems, significant coarsening occurs. Both results from bubble-scale and the bulk-scale experiments suggest that compatibility experiments are pre-requisite to foam stability analysis to test the compatibility between surfactants and nanoparticles.

Keywords: Foam stability; Diffusional coarsening; Bubble coalescence; Gravitational drainage; Nanoparticle; Surfactant

Domains: Hydrology; Geochemistry; Other

Mohammad Javad Shojaei, Yves Méheust, Abdulkadir Osman, Paul Grassia, Nima Shokri. Combined Effects of Nanoparticles and Surfactants upon Foam Stability. Chemical Engineering Science, 2021, 238, pp.116601. ⟨10.1016/j.ces.2021.116601⟩. ⟨insu-03178786⟩