Measuring Interfacial Tension Between Oil and Nano-Saline Solutions in the Presence of SiO₂ or TiO₂ at Low and Intermediate Pressures

In this paper, SiO₂ and/or TiO₂ nanoparticles (NPs) were used to enhance the performance of water injection process causing an increase in oil recovery. To this end, several nano saline solutions were prepared from each of the following salt compounds: NaCl, CaSO₄, or MgSO₄ (1000 ppm) together with different concentrations of SiO₂ and/or TiO₂ NPs from 0.01 to 0.07 wt.%. Interfacial tensions (IFT) between the oil, collected from Sarvestan oil reservoir, and the saline solutions were measured at low and intermediate pressures, i.e. 14.5, 72.5, 145, 217.5, 290, 362.5, 435, 507.5, and 1160 Psi using a homemade IFT-device. Results showed that SiO₂ and/or TiO₂ NPs successfully reduced the interfacial tension between the oil and the saline solutions. The maximum reductions of 63.95% and 63.46% were obtained at the pressure of 507.5 Psi for 0.05 wt.% of SiO₂ in the MgSO₄-H₂O solution and 0.05 wt.% of TiO₂ in the CaSO₄-H₂O solution, respectively. The maximum IFT reductions for NaCl-H₂O-TiO_2, NaCl-H₂O-SiO₂, MgSO₄-H₂O-TiO₂, and CaSO₄-H₂O-SiO₂ solutions were 58.13%, 49.65%, 36.18%, and 20.88%, respectively.