The Wettability of Surfactant Solutions on Particles in Simulated Reservoirs
摘要
The study employed the Washburn capillary rise method to investigate the wettability of three conventional surfactants-cationic surfactant cetyltrimethylammonium bromide (CTAB), anionic surfactant sodium dodecyl sulfate (SDS), and nonionic surfactant Triton X-100 (TX-100)-on powders with varying polarities, and to examine the behavior of droplets under capillary force. For kaolin, illite, and silica nanoparticles, CTAB's hydrophilic portion interacted with the powders through electrostatic forces. TX-100 adhered to solid particles via hydrophilic epoxy groups and hydrogen bonding interactions, while SDS attached to hydrophilic particles through hydrophobic groups and Lifshitz-van der Waals forces. In the case of hydrophobic oil sands, CTAB, SDS, and TX-100 exhibited adsorption through hydrophobic interactions. At the critical micelle concentration (CMC), surfactant molecules aggregated to form micelles, affecting solution mobility and altering wetting properties such as contact angles. This study highlights the dynamic interplay between surfactant solution surface tension, solid-liquid interfacial tension, and their effects on wetting behavior across different solution concentrations. The competitive dynamics between adsorption and surface tension significantly influence the wetting behavior of surfactant solutions.