Zeta-potential investigation and experimental study of nanoparticles deposited on rock surface to reduce fines migration

Finesmigration is a noticeable problem in petroleum-production engineering. Plugging of throats in porous media occurs because of detachment of fine particles from sand surfaces. Thus, the study of interactions between fines and pore surfaces and the investigation of governing forces are important factors to consider when describing the mechanism of the fines-release process. The main types of these forces are electric double-layer repulsion (DLR) and London-van der Waals attraction (LVA). It may be possible to alter these forces with nanoparticles (NPs) as surface coatings. In comparison with repulsion forces, NPs increase the effect of attraction forces. In this paper, we present new experiments and simple modeling to observe such properties of NPs. For this purpose, the surfaces of pores were coated with different types of NPs: magnesium oxide (MgO), silicon dioxide (SiO₂), and aluminum oxide (Al₂O₃). A zeta-potential test was used to examine changes in the potential of the pore surfaces. Total interaction energy was then mathematically calculated to compare different states. Total interaction energy is a fitting criterion that gives proper information about the effect of different NPs on surface properties. Consequently, total interaction plots are found to be suitable tools for selecting the best coating material. On the basis of experimental results, the magnitude of change in zeta potential for the MgO NP was 45 mV. Our model demonstrated that the magnitude of the electric DLR in comparison with the LVA of the probe and plate surface was considerably diminished when MgO NPs were used to coat the surface of the plate, which agrees completely with our experimental observation.