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 (MD_dose), the concentration of oil (C_oil), pH, the concentration of the surfactant (C_sur), and separation time (t_sep) on the demulsification efficiency (%η_dem), and the percentage of oil recovered (%R_oil) were evaluated. An excellent %η_dem ≥ 90% was achieved C_oil in the range 50 to 2000 mg/L. Using an MD_dose as low as 10 mg/L attained a %η_dem in the range of 93% to 94.3% for O/W mixtures with C_oil < 2000 mg/L, which slightly decreased to ∼ 90% for higher concentrations. The reported %R_oil (p-value <0.05) was > 90 ± 0.1 for tests carried out with pH ≤ 7 and C_sur ≤ 0.1 g/L and declined at higher pH and C_sur to % 86.5 due to the increase in emulsion stability. The developed MD exhibited high recyclability at an effective and stable %R_oil and %η_dem of ∼ 90% and 86.4 % after 9 cycles, respectively. Demulsification process best fits the combined Langmuir-Freundlich (L-F) isotherm with highest adsorption capacity (Q_max) of 186.0 ± 5 mg_oil/g_MD compared to 86.0 ± 5 mg_oil/g_MD for Fe₃O₄, which is 1.1 folds greater than Q_max reported in the literature for other demulsifiers.

在这项研究中，通过使用改良的Stober工艺将二氧化硅层接枝到Fe ₃ O ₄磁性纳米颗粒（MNP）的表面上，制备了创新的磁性破乳剂（MD）。MD使用各种分析技术（XRD，FTIR，TGA，TEM，VSM等）进行了表征，并用于从O / W乳液中回收油，然后对其进行再生和再循环。磁性破乳剂的用量（MD_剂量），油的浓度（C_油），pH，表面活性剂的浓度（C _sur）和分离时间（t _sep）对破乳效率（％_ηdem）的影响，以及回收油的百分比（％R_油）进行了评估。在50至2000 mg / L的范围内，C_油的％_ηdem≥90％。对于C_油<2000 mg / L的O / W混合物，使用低至10 mg / L的MD_剂量可获得的％_ηdem在93％至94.3％的范围内，对于较高浓度的O / W混合物，其％ηdem略微降低至〜90％。所报告的％R_油（p-值<0.05）> 90±0.1用于测试随pH≤7和C进行_河畔≤0.1 g / L和在更高的pH和C下降_河畔到％86.5由于增加乳液稳定性。在有效稳定的％R_油和％_{ηdem的条件下}，开发出的MD具有较高的可回收性在9个循环后分别达到约90％和86.4％。破乳工艺最适合组合的Langmuir-Freundlich（LF）等温线，其最高吸附容量（Q _max）为186.0±5 mg_油/ g _MD，而Fe ₃ O _4的吸附容量为86.0±5 mg_油/ g _MD，是1.1倍大于文献中报道的其他破乳剂的Q _max。