A study of interfacial dilational properties of two different structure demulsifiers at oil–water interfaces

Aqueous foam stabilized by partially hydrophobic nanoparticles in the presence of surfactant

“…When the SDS concentration was high enough, the absorbed SDS was nearly saturated. An increase in the bulk concentration could only increase the trend of the diffusion of SDS molecules from the bulk to the interface and compensate the surface tension gradients, which significantly decreased the dilational viscoelasticity [33]. The maximum value of ε for SiO 2 /SDS dispersions appeared at the SDS concentration of 0.05 wt%, and it was bigger than that of SDS solution.…”

“…For SDS solution, the maximum value appeared at the concentration of 0.10 wt%. Generally, an increase of the SDS concentration affects the dilational viscoelasticity in two aspects [33]: increase of the interfacial surfactant concentration, and enhanced diffusion of surfactant molecules from the bulk solution to the new interface. At low SDS concentration, the increase of interfacial surfactant concentration would cause higher surface tension gradient during the interface deforming, which in turn increased the dilational viscoelasticity [34].…”

Demulsification Mechanism of Asphaltene-Stabilized Water-in-Oil Emulsions by a Polymeric Ethylene Oxide–Propylene Oxide Demulsifier

“…A second deformation of the interface that can contribute to droplet stability is the compressional response of the interfacial film. 18 Specifically, low interfacial film rigidity under compression is reported to favor droplet coalescence 50,51 .…”

Effect of the structure of commercial poly(ethylene oxide-b-propylene oxide) demulsifier bases on the demulsification of water-in-crude oil emulsions: elucidation of the demulsification mechanism

“…Some researchers state that the demulsifier replaces the emulsifier at the interface since the interfacial elasticity decreases. 38,39 Sun et al concluded that the demulsifier leaves small voids at the interface after occupying the water droplet surface, which keeps out the emulsifiers from the interface. 40 Ese et al suggested that the demulsifier disperses the asphaltene aggregates like resins do, 41 as the images from atomic-force microscopy (AFM) of asphaltene films showed an open structure with regions completely uncovered when 100 ppm of demulsifier was added, similar to the effect of resins.…”