In Situ Investigation on the Effect of Salinity and pH on the Asphaltene Desorption under Flowing Conditions

There is a limited understanding of the microscale interactions between fluid-oil-solid interfaces, which could be a stumbling block to the development of relevant technologies and industries. With this in mind, we applied an in situ method, quartz crystal microbalance with dissipation (QCM-D), on the interactions among the fluid-oil-solid phases and investigated the desorption process of the asphaltene model molecule from silica surfaces during a flow of LSW at the conditions of different ion types, salinities, or pH values. The salinity effect plays a bigger role than that of the pH effect on the asphaltene desorption and, furthermore, the divalent ions (such as SO42-, Mg2+, or Ca2+) show a stronger effect than that of monovalent ions (such as Cl-, Na+, or K+). Our study provides a new strategy for the investigation of the interactions between fluid-oil-solid interfaces.