Interactions between chloride-based salts (CaCl2 and MgCl2), ionic liquids, pH, and titanium oxide nanoparticles under low and high salinity conditions, and synthetic resinous crude oil: dorud oilfield

Abstract

Unfortunately, oil reservoirs are complex considering the fluids (e.g., crude oil composition) and rock properties making it hard to propose a simple enhanced oil recovery (EOR) method for higher oil production. Besides, most of the investigations had focused on crude oil which is a complex mixture of thousands of components making it hard to extract any reliable conclusions with respect to the crude oil type. So, the current study is focused on the application of ionic liquids from different families of pyridinium and imidazolium, titanium oxide nanoparticles, and salts (MgCl₂ and CaCl₂) in the presence of resinous synthetic oil for the first time. The obtained results using the central composite design (CCD) approach revealed the positive effect of resin fraction on the IFT reduction by 27% considering the initial value (34.9%). Using the CCD approach revealed that using pH = 7, MgCl₂ concentration = 21,000 ppm, CaCl₂ concentration = 21,000 ppm, resin fraction of 9wt%t and 500 ppm of [C₁₂mim][Cl] concentration reduces the IFT to minimum value of 0.62 mN/m while the minimum IFT value for optimum conditions of solution includes [C₁₂py][Cl] led to minimum IFT value of 2.2 mN/m. But, the contact angle measurements revealed better synergy between [C₁₂py][Cl] and TiO₂-NPs (0–200 ppm) for better wettability alteration toward water-wet condition (27.3°) than [C₁₂mim][Cl] (33.2°). Moreover, the IFT measurements revealed that the presence of TiO2-NPs is effective in reducing the IFT of the optimum formulations to 0.55 and 0.84 mN/m for [C₁₂mim][Cl], and [C₁₂py][Cl], respectively. According to the results, it seems that the obtained optimum formulations for [C₁₂mim][Cl], and [C₁₂py][Cl] are applicable for EOR purposes as new hybrid solutions.