تحضير وتوصيف جزيئات أكسيد الحديد النانوية واستخدامها في إزالة صبغة الا يوسين الصفراء من المحاليل المائية

Rp-Preparation, Characterization of Iron Oxide Nanoparticles, and use in the Removal of Eosin Yellow Dye from aqueous solutions.pdf

This work includes three routes, the first used an innovative precipitation method for creating magnetic Fe3O4 nanoparticles under environment oxygen without and with the use of different surfactants as templates, including sodium dodecyl sulfate (SDS), triton X100, cetrimonium bromide (CTAB), and cetramide (CT). These magnetic iron oxide (Fe3O4) nanoparticles were created as inverse spinel (Fe2O3. FeO), when combined iron sulfate solution with an aqueous mixture of sodium hydroxide and sodium nitrate without any calcination under oxygen gas. In second route, the prepared iron oxide nanoparticles (Spinel Fe3O4) were identified using several techniques, including infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis, and scanning electron microscopy (SEM). Infrared spectroscopy showed reasonable peaks at 598-744 cm-1, confirming the presence of the tetrahedral and octahedral structures of the prepared iron oxide nanoparticles as an inverse spinel. X-ray diffraction explained that the prepared samples without and with addition surfactants are crystalline in nature, with nanosize ranged (8.5 nm without surfactants to 27.72 nm with using the surfactants). SEM images of prepared iron oxide nanoparticles without and with using surfactants given spherical shapes with semi-regular clusters as Broccoli like nanostructures. On the other hand in third route, iron oxide nanoparticles were used as an adsorbent to remove eosin yellow dye from aqueous solutions. In the beginning, an adsorption experiment was conducted for all the prepared surfaces towards the dye, as it was found that the best removal percentage of the dye was on the surface of iron oxide nanoparticles with cetrimide (Fe3O4 + cetramide), where the removal percentage reached 94.7% . After that, the factors affecting the surface adsorption process of iron oxide were studied with cetrimide only, Fe3O4 prepared with cetramide gave a higher removal efficiency compared with the prepared iron oxides. It was found that the adsorption capacity increased with the increase of the equilibrium time until it reached the saturation stage at a time of 60 minutes. While testing the effect of the amount of surface on the adsorption process showed an increase in the removal efficiency with the increase in the surface mass as a result of the increase in the surface area, the dye was most effectively absorbed at a weight of 0.01 g. The pH factor showed a clear effect on the removal efficiency, as it was found that the best removal of the dye in a neutral medium (pH 6.5) is due to the presence of neutralizing groups in the composition of eosin yellow dye. On the other hand, it was found that the removal efficiency increases with the increase in temperature as a result of the increase in kinetic energy, which facilitates the access of dye molecules to the active sites on the adsorbent surface. The thermodynamic study showed that the process of adsorption of iron oxide nanoparticles with cetrimide is an endothermic process since the enthalpy value is positive and spontaneous and does not require an external source, while the enthalpy value is negative and non-spontaneous in the creation of iron oxide nanoparticles without cetrimide is an exothermic process. Magnetite with cetramide obeys a chemisorption because ΔHo of this reaction is more valuable than (20) kJ mol-1 in opposite the Fe3O4 in absence cetramide is found to be Physisorption because ΔHo value is lower than (20) kJ mol-1. The data from the isotherm model equations show that the magnetite produced in the presence of cetramide obeys Langmuir, Freundlich, and Temkin while Fe3O4 produced in the absence of cetramide does not.