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

Abstract

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 SO4 2–, 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.

Understanding the Adsorption and Desorption of Sitagliptin Phosphate Monohydrate on SS2343, Glass, and PTFE Using QCM-D and Raman Spectroscopy

“…In recent years, the quartz crystal microbalance with dissipation (QCM-D) has been extensively used in many studies for the evaluation of the interactions of molecules on various surfaces, , including cleaning of surfaces. , QCM-D works by mechanical deformation in response to the electric field applied . Therefore, masses as small as in the nanogram range when added or removed from the QCM-D sensor will produce different signals, i.e., in the form of frequency change (Δ f ) and dissipation change (Δ D ) at different resonances .…”