Differences of oil movement through micro channels after surfactant addition in the presence of silica nanoparticles, compared to the surfactant alone. Image credit: Goshtasp Cheraghian/Azad University/IranNanoparticle-surfactant complexes could be the key to improving the yield of enhanced oil recovery (EOR) technologies. Material composed of sodium dodecyl sulfate (SDS) surfactant and fumed silica nanoparticles (Si-NPs) have been shown to increase oil recovery to 58 percent compared to 45 percent recovery in the presence of surfactant alone.

The materials fabricated by researchers from Swansea University (Wales) and Islamic Azad University (Iran) were tested in a five-spot glass micromodel to evaluate suitable agents for oil displacement in EOR. Such experiments have been used to investigate the mechanism of fluid flow on porous media via flow visualization, pore space geometry, topology and heterogeneity effects, which are not possible to assess using traditional core-flood experiments.

The addition of the fumed silica to the EOR agent was demonstrated to increase the proportion of oil recovered, enabling a further 13 percent enhancement in oil recovery for the maximum 2.2 wt. percent concentration of the SDS/Si-NPs, as well as a delay in the breakthrough point.