Dewetting Dynamics of a Solid Microsphere by Emulsion Drops

Abstract

A novel micropipet technique was developed to quantify the dewetting dynamics of individual microsphere particles by emulsified viscous crude oil drops in aqueous media. This technique allowed dynamic microscale receding contact angles of water to be measured in situ for solid−oil−water systems. System parameters, including modification of glass microspheres and characteristics of oil drops, were varied to study their effect on dewetting dynamics of the systems. Increasing solvent dosage in viscous oil was found to decrease static receding contact angle of water for clean and bitumen-treated glass surfaces, but showed a negligible effect on static receding contact angle for ethyl cellulose (EC)-treated glass surface. Interestingly, dynamic dewetting behavior exhibited a strong dependence on surface modification and the addition of solvent to viscous oil. No dewetting dynamics was observed for clean hydrophilic glass surface. For bitumen-or EC-treated glass surfaces, more rapid dewetting dynamics of water were determined with increasing addition of solvent to viscous oil. Both de Gennes viscous dissipation hydrodynamic and the Blake/Haynes molecular-kinetic models were developed for the current system to understand the observed dynamic dewetting characteristics.

Effect of solvent addition on bitumen–air bubble attachment in process water

“…These studies demonstrated that bitumen could be competently recovered from oil/tar sands at a lower temperature with the assistance of a process aid. Recently, the working mechanisms of enhancing bitumen liberation -another essential step of bitumen extraction from oil sands via the addition of process aids including toluene, naphtha have been derived to guide design and selection of process aids Lin et al, 2014). To our best knowledge, there exists little information in open literature on the role of adding process aids in bitumen-air bubble interaction and attachment in water.…”

Impact of salinity on warm water‐based mineable oil sands processing

“…the angle between the two tangent lines at the three phase contact (TPC) point) were obtained by applying the automated angle acquisition method to analyzing still images, from which the dynamic and equilibrium contact angles were obtained. An example of this analysis on a real image is shown in Figure …”

“…A typical image analysis of contact angle determination using an in‐house developed shape fitting method …”

“…[19,20] The details on the procedures of droplet relaxation experiment were already given elsewhere. [19,20] Only a brief description is given here. A micronscale, ball-shaped glass tip was coated in air with vacuum distillation feed bitumen (VDFU) provided by Syncrude Canada Ltd.…”

“…An example of this analysis on a real image is shown in Figure 2. [19,20] Induction time measurement…”