Disjoining Pressure Isotherms of Water-in-Bitumen Emulsion Films

Oilfield solids and water-in-oil emulsion stability

“…Persistent emulsion stability is often attributed to a rigid, viscous film that surrounds water droplets and prevents their coalescence [1][2][3][4][5][6]. Most often the interface is cited as containing surface-active species such as asphaltenes and resins [6][7][8][9] and biwettable particles such as the native sands and clays associated with heavy crude chances of segregation of water and oil. The mechanisms associated with solids-stabilized emulsions and the degree to which solids increase emulsion stability depend on several factors such as particle size, shape and morphology, density, concentration and surface coverage, and wettability.…”

“…Protective coatings or "skins" are thought to be responsible for the mechanical strength of interfaces [4,5,9,[45][46][47][48]. Recent work has quantified some of these effects and in fact suggested that emulsion stability is due to high elasticity of the interface [49].…”

Understanding Mechanisms of Asphaltene Adsorption from Organic Solvent on Mica

“…The interactions and assembly of adsorbed molecules or their aggregates lead to formation of a protective layer that resists droplet-droplet coalescence. [1][2][3][4][5][6][7][8][9][10][11] Stable emulsions have been a major challenge in petroleum production, affecting process throughput and downstream operations such as upgrading. It is necessary to develop knowledge on the formation of these protective layers to design suitable protocols for film disruption and prevention of stable emulsion formation.…”

Superstabilization of emulsions by solid particles

“…Hexylamine constitutes a separate bulk layer that becomes visible at concentrations above 0.151 mol/L. Hexylamine-water nanoemulsion instability is associated with a large interfacial tension between water and hexylamine, approximately 50 mN/m [10].…”

“…However, proteins and surfactants do not possess the full properties of course particles, as globular micelle proteins are more susceptible to deformation and can change their conformation on the liquid surface. Additionally, adsorbed protein layers are viscoelastic and flexible [9], whereas adsorbed solid partiсle layers are rigid shells [10][11][12][13]. Thus, shells, or "skins," of solid particles can form on emulsion drops [10].…”