Surface tension and wettability analysis during the interaction of alkali-nano silica and its effect on acidic crude oil

Among several chemical flooding methods, alkaline flooding is widely used for the recovery of acidic crude oil. Earlier studies showed fewer applications on high incremental oil recovery over water-flooding. To recover a maximum amount of crude oil, different methods are employed. Alkaline flooding is one of the most common techniques to recover the remaining trapped oil from the reservoir. In this study, experiments are carried out to study the physicochemical properties of an alkali-nano-silica solution, such as surface tension, wettability analysis, and pH. After inspecting the results, we find that the presence of nano-silica plays a significant role in alkaline flooding. The surface tension decreases on increasing the concentration of NaOH/KOH solution for all concentrations. A decrease in the value of the contact angle with time is observed, which indicates that the alkali drop can displace the oil from the surface of the sandstone. This is a clear indication that the alkali solution can transfer the oil from the core sample’s surface. These results show that if nano-silica is added to an alkaline solution, it can enhance the acidic oil recovery. The process for this can be adequately designed and controlled. The results discussed herein also facilitate understanding the use of alkali in the treatment of oil spilled in water during offshore drilling or from the offshore storage facility. Graphical abstract