Synthesizing CNT/MgO nanocomposite to form stable pickering emulsion at high temperature and salinity and its application to improved oil displacement efficiency

In this work CNT/MgO nanocomposites is synthesized to investigate their effect on oil displacement efficiency in porous media. Characterization methods confirmed that the CNT/MgO nanocomposite is synthesized successfully where the MgO nanoparticles covered the CNTs homogenously. The stability of the formed emulsions confirmed that the CNT/MgO nanocomposite form stable emulsions at high temperatures and salinity conditions. It was found that while using this nanocomposite, the interfacial tension (IFT) is reduced significantly. Moreover, the contact angle measurements proved that the synthesized nanoparticle is able to alter the wettability of the porous media from the oil-wet condition to the water-wet condition, which is highly demanded in the EOR application. As a dynamic method to investigate the EOR mechanism of nanofluid injection, microfluidic flooding method is employed to verify the result of static tests and show the potential of the prepared nanocomposites on enhancing the recovery factor. It is observed the investigated nanofluid with a concentration of 0.5 wt%‌ provides a higher recovery factor (about 60%) in comparison to deionized water flooding (about 20 %). • Synthesizing the CNT/MgO to investigate the oil displacement in porous media. • Stable emulsions formation at high temperatures and salinity using CNT/MgO. • The CNT/MgO alters the wettability from the oil-wet to the water-wet. • Nanofluid with a concentration of 0.5 wt%‌ provides a higher recovery factor (60 %).