Investigation of the effect of Fe3O4/SiO2 nanofluid on asphaltene adsorption and wettability alteration in hydrocarbon reservoirs: Optimization of nanocomposite composition and nanofluid concentration

Abstract

One of the most efficient ways to extract hydrocarbons is to use nanoparticles for wettability alteration, to address dwindling reservoirs and growing energy demand. Another crucial factor is inhibiting asphaltene precipitation, which can cause damage to production components and alter the rock's wettability and permeability. This study investigates the impact of synthesized Fe3O4, SiO2, and Fe3O4/SiO2 nanomaterials on wettability alteration and asphaltene removal in an oil/water system at two temperatures (25 °C and 80 °C). The nanocomposites with various ratios were manufactured with the aid of the sol-gel method and characterized using FTIR, XRD, and dynamic light scattering analysis. The stability of different concentrations of nanofluids was assessed via sedimentation tests and zeta potential measurements. According to the results, there was a reduction in both surface energy and oil area fraction from 89.46 to 8.13 mN/m and from about 1–0.075, respectively. Maximum wettability alteration (from 155° to 32°) was achieved at the optimum condition (0.075 wt% of C1000 at 80 °C). The C1000 nanocomposite played a significant role as an inhibitor in shifting the onset point to higher concentrations of n-heptane compared to Fe3O4 and SiO2 nanoparticles. Furthermore, nanomaterials have a better association with the Langmuir model, and the asphaltene particles are adsorbed homogeneously and in the form of one layer of adsorbents. The results of this study can assist the petroleum sector in better controlling asphaltene precipitation and enhancing oil recovery by C1000 nanoparticles, leading to a higher recovery rate and a more cost-effective production approach.