Application of Functionalized Fe₃O₄ Magnetic Nanoparticles Using CTAB and SDS for Oil Separation from Oil-in-Water Nanoemulsions

Abstract

Using magnetic nanoparticles (MNPs) for emulsified oil separation from wastewater is becoming increasingly widespread. This study aims to synthesize MNPs using amphiphilic coatings to stabilize the MNPs and prevent their agglomeration for efficiently breaking oil-in-water nanoemulsions. We coat two different sizes of Fe 3 O 4 nanoparticles (15−20 and 50−100 nm) using cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) with surfactant-to-MNP mass ratios of 0.4 and 0.8. We study the effect of various variables on the demulsification performance, including the MNP size and concentration, coating materials, and MNP loading. Based on the oil−water separation analysis, the smaller size MNPs (MNP-S) show a better demulsification performance than the larger ones (MNP-L ) for a 1000 ppm dodecane-in-water emulsion containing nanosized oil droplets (250−300 nm). For smaller MNPs (MNP-S) and at low dosage level of 0.5 g/L, functionalizing with surfactant-to-MNP mass ratio of 0.4, the functionalization increases the separation efficiency (SE) from 57.5% for bare MNP-S to 86.1% and 99.8 for the SDS and CTAB coatings, respectively. The highest SE for MNP-S@CTAB and the zeta potential measurements imply that electrostatic attraction between negatively charged oil droplets (−55.9 ± 2.44 mV) and positively charged MNP-S@CTAB (+35.8 ± 0.34 mV) is the major contributor to a high SE. Furthermore, the reusability tests for MNP-S@CTAB reveal that after 10 cycles, the amount of oil adsorption capacity decreases slightly, from 20 to 19 mg/g, indicating an excellent stability of synthesized nanoparticles. In conclusion, functionalized MNPs with tailored functional groups feature a high oil SE that could be effectively used for oil separation from emulsified oily wastewater streams.

Comparative Study of Amino-Functionalized Magnetic Mesoporous Arrangements for the Remediation of Persistent Organic Pollutants from Water Using Response Surface Methodology

“…These mesoporous materials have versatility and multifunctionality as main characteristics, so they are applied in the most varied applications in the literature. , Nowadays, a trend in the scientific community is the preparation of these mesoporous materials functionalized with magnetic nanoparticles (MNPs), especially those based on the mineral structure of spinel (MgAl 2 O 4 ), the so-called ferrites, mainly those with a structure similar to the CoFe 2 O 4 . These MNPs have several important properties, especially easy separation under magnetic field and high adsorption efficiency. − Thus, in the present approach, we developed magnetic mesoporous materials based on the MCM-48 cubic structure functionalized with CoFe 2 O 4 MNPs to be used in the remediation of the different organic pollutants.…”

Olive stone as an eco-friendly bio-adsorbent for elimination of methylene blue dye from industrial wastewater

“…Studying the key process variables demonstrates that OS is an effective material in removing the MB dye, with a good removal efficiency equal to 93.65% compared to other low-cost adsorbents such as pine leaves 21 and pine cone 22 with the removal efficiencies equal to ~ 80% and 63.83–94.82%, respectively, (Table 1 ).…”

“…MB is used in various fields, such as biology, medicine, and chemistry 12 . Wastewater is treated using different methods, such as membrane separation 13 , 14 , electrocoagulation 15 , 16 , flocculation 17 , precipitation 18 , ozonation 19 , and adsorption 20 , 21 . These well-established methods frequently fail to lower dye concentrations to desirable levels and are not economical for dye removal.…”

“…Examples of low-cost adsorbents include pine leaves, pine cones, rice hull, tectona grandis sawdust, prickly pear seed cake, apricot seed, and sugarcane bagasse. These adsorbents showed promising results in removing several dyes such as Methylene Blue, Reactive Orange 16, Crystal Violet, Methyl Orange, Astrazone Black and Rhodamine B 21 – 27 . Table 1 presents the results of various reported studies of low-cost adsorbents on removal efficiency.…”