Abstract
Nanoparticles and nanocomposites have been used in recent studies to improve oil reservoir recovery. With the introduction of a newly constructed smart water injection scenario, this work investigated the physicochemical characteristics of the polymeric carbon nitride/ZrO(2) nanocomposite (ZrO(2)/g-C(3)N(4)), and the results were compared with pure ZrO(2) nanoparticles as a known enhanced oil recovery agent. The effects of ZrO(2)/g-C(3)N(4) and ZrO(2) on the wettability change, zeta potential, and interfacial tension under reservoir conditions (78 °C and 3800 psi) were determined after characterization experiments, which included X-ray powder diffraction (XRD), a Fourier transform infrared spectrometer (FTIR), transmission electron microscopy (TEM), a field emission scanning electron microscope (FESEM), energy-dispersive x-ray testing (EDX), and a Brunauer-Emmett-Teller (BET) analysis. Based on the highest zeta potential and the greatest reduction in the contact angle and interfacial tension, the optimum concentrations for ZrO(2)/g-C(3)N(4) and ZrO(2) were determined to be 30 and 40 ppm, respectively. Moreover, the ZrO(2)/g-C(3)N(4) nanocomposite demonstrated better results in enhancing the oil recovery parameters, and it was selected for low salinity flooding scenarios with three different salinities, including MgCl(2) + seawater (SW), CaCl(2) + SW, and MgSO(4) + SW, at 30 ppm of the nanocomposite. The best readings for the ZrO(2)/g-C(3)N(4) nanocomposite in its interfacial tension, contact angle, and zeta potential show that 1000 ppm has the best interfacial tension reduction among the tested concentrations of 500-50,000 ppm. At 30 ppm, MgCl(2) + SW had the maximum recovery (i.e., 49.36%), and this resulted from better interfacial tension reduction, contact angle reduction, and stability compared to other salinities.