RESUMEN
Nanofluids have shown their potential in the oil recovery process through surface modification. Due to their surface characteristics, they can apply to improve the oil production from reservoirs by enabling different enhanced recovery mechanisms. The preparation and development of the Fe3O4@SiO2 nanoparticles for the oil recovery process is an innovative and novel approach that influences the oil generation from reservoirs. The performance of the Fe3O4@SiO2 and the other nanofluids (seawater, Fe3O4, and SiO2) in the enhanced oil recovery process is assessed and compared with other flooding scenarios. The Fe3O4@SiO2 NPs achieved the highest oil production rate of 90.2% while Fe3O4 and SiO2 NPs achieved 70.8% and 55.3%, respectively. In contrast, the value achieved for the seawater injection was 76.5%. For the oil recovery process, the Fe3O4 was applied for the inhibition (i.e., decrease) of oil sedimentation, and the SiO2 NPs were applied for wettability alteration and IFT reduction. The experimental results showed that the produced Fe3O4@SiO2 NPs improved the oil recovery rates (90.2%) as well as the synergetic impact of the developed NPs by initiating several mechanisms corresponding to the use of the separate NPs in the micromodel. Moreover, the results exhibited that the reservoir conditions are a crucial function for increasing the oil recovery rates, improving the emulsion stability, and acts as a substantial step for the oil recovery method that applies this particular technique.
Asunto(s)
Nanopartículas , Dióxido de Silicio , Emulsiones , HumectabilidadRESUMEN
Functionalized Fe3O4-SiO2 magnetic nanoparticles (Fe-Si-MNPs) coated with hyperbranched polyglycerol polymer were prepared and tested for oil recovery from oil in water (O/W) emulsions. The structure, chemistry, and surface modifications of the newly developed demulsifier (PSiMNPs) were analyzed, and the percentage demulsification efficiency (%ηdem) was tested at differing concentrations of surfactant (Csur), oil (Coil), and demulsifier (DPSiMNPs). The developed PSiMNPs can be separated from the solution by a magnetic field, regenerated using ethanol, and reused several times. The reported %ηdem was ≥80% for all the studied Coil. The %ηdem improved as the Csur and pH decreased, with maximum values of 98.8% and 98.5% achieved at Csur = 0.05 g/L and a pH = 4, respectively. A DPSiMNPs = 100 mg/L was sufficient to achieve %ηdem of 99.4% for Coil = 100 mg/L and slightly decreased to ~93% for Coil ~4000 mg/L. The PSiMNPs can be reused up to 15 times with a steady %ηdem of 89.1% for Coil = 100 mg/L and 88.6% for Coil = 4000 mg/L. The adsorption of oil on the PSiMNPs follows Freundlich isotherm with maximum adsorption capacity (qmax) of 192.8 g/mg and Langmuir constant (b) of 28.06 mg/L for Coil = 900 mg/L. The qmax of the recycled PSiMNPs slightly decreased to 189.08 g/mg. The kinetic of oil recovery follows the PSO with a K2 of 0.0169 g/mg. min. Surface modification of Fe-Si-MNPs enhanced the oil adsorption, increased the adsorption capacity, and extended the service life resulting in a better cost and process feasibility.
Asunto(s)
Nanopartículas , Dióxido de Silicio , Adsorción , Glicerol , PolímerosRESUMEN
This study presents an innovative approach for the preparation of Fe3O4 nanoparticles covered with SiO2 shell (denoted as Fe-Si-MNP), which were used to recover oil recovery from oil-in-water emulsion (O/W-emul). The Fe-Si-MNP were prepared with differing silica layer thicknesses (5 nm [Fe-Si-1], 8 nm [Fe-Si-2], 10 nm [Fe-Si-3], and 15 nm [Fe-Si-4]) and tested for the percentage of oil separation (%Soil) under different dosages (DMNP), oil concentration (Doil), surfactant dosages (Dsur), and pH. The Fe-Si-MNP exhibited excellent %Soil, reliable stability, and high magnetization values ranging between 46.1 and 80.2 emu/g. adding a 5 nm silica layer on the surface of the Fe-Si-MNP (i.e., Fe-Si-1) protected them from oxidation conditions, extended their service life, and achieved a %Soil of â¼96.3%. The %Soil slightly decreased to â¼92% with an alkaline pH or when the thickness of the silica layer increased to ≥10 nm. The %Soil was 90.5%, 89.5%, and 87.5% for Fe-Si-2, Fe-Si-3, and Fe-Si-4, respectively. Increasing the water salinity from 0.1 to 0.5 M slightly improved the %Soil for the tests carried out with a Doil of 100 mg/L to 93.3%, 90.3%, and 86.3% for Fe-Si-2, Fe-Si-3, and FeSi-4, respectively. The highest %Soil achieved with Fe- Si-1 Fe-Si-2 and Fe-Si-3 was >95%, 95% and 92%, respectively. The Fe-Si-MNP exhibited a high recyclability for 9 cycles with the lowest %Soil â¼80%. The results suggest that the structure and properties of the Fe-Si-MNP can be manipulated to achieve a high oil recovery, easy separation, and extended service life.
Asunto(s)
Nanopartículas de Magnetita , Dióxido de Silicio , Emulsiones , Magnetismo , AguaRESUMEN
In this study, an innovative magnetic demulsifier (MD) was prepared by grafting a silica layer onto the surface of the Fe3O4 magnetic nanoparticles (MNPs) using the modified Stober process. The MD was characterized using various analytical techniques (XRD, FTIR, TGA, TEM, VSM, etc.) and employed to recover oil from O/W emulsion, which were then regenerated and recycled several times. The effects of magnetic demulsifier dosage (MDdose), the concentration of oil (Coil), pH, the concentration of the surfactant (Csur), and separation time (tsep) on the demulsification efficiency (%ηdem), and the percentage of oil recovered (%Roil) were evaluated. An excellent %ηdem ≥ 90% was achieved Coil in the range 50-2000 mg/L. Using an MDdose as low as 10 mg/L attained a %ηdem in the range of 93%-94.3% for O/W mixtures with Coil < 2000 mg/L, which slightly decreased to â¼90% for higher concentrations. The reported %Roil (p-value <0.05) was >90 ± 0.1 for tests carried out with pH ≤ 7 and Csur ≤ 0.1 g/L and declined at higher pH and Csur to % 86.5 due to the increase in emulsion stability. The developed MD exhibited high recyclability at an effective and stable %Roil and %ηdem of â¼90% and 86.4% after 9 cycles, respectively. Demulsification process best fits the combined Langmuir-Freundlich (L-F) isotherm with highest adsorption capacity (Qmax) of 186.0 ± 5 mgoil/gMD compared to 86.0 ± 5 mgoil/gMD for Fe3O4, which is 1.1 folds greater than Qmax reported in the literature for other demulsifiers.