Modification of LoSal water performance in reducing interfacial tension using green ZnO/SiO₂ nanocomposite coated by xanthan

Interfacial tension (IFT) is one of the most important factors that affect oil production mechanisms in porous media. Nanoparticles show potential for high performance in IFT reduction, wettability alteration and enhanced oil recovery. The current work focuses on the simple, economical and, importantly, green method of biosynthesis to generate a nanocomposite (NC) for reducing the IFT in enhanced oil recovery. In this study, ZnO@SiO ₂ @Xanthan NC was created from pomegranate sed extract and characterized by various analytical techniques. The nanofluids were prepared by varying the concentration of NC to find the optimum value of IFT reduction under different conditions of salinity, temperature and pressure. The results showed that by applying this nanocomposite at a concentration of 2000 ppm into a low salinity (LoSal) water at high temperature and pressure, the IFT reduced by 93.6% from 31.8 (for seawater) down to 2.016 mN/m. Further IFT reduction was obtained by the NC as the salinity of water was decreased and the temperature and concentration of NC were increased although there was no clear trend with pressure.