The Chemical Engineering Department at the College of Engineering, University of Baghdad, held a M.Sc. thesis examination titled:
“ Oil Spill Cleanup using Magnetic Nanoparticles ”
By the student “Maha Jalal Awda” and supervised by Prof Dr. Basma Abbas Abdulmajeed. The examination committee consisted of Prof. Dr. Muthana Jabbar Ahmed as Chairman and the membership of Asst. Prof. Dr. Yassir Imad Abdulziz, Asst. Prof. Dr. Asrar Abdullah Hassan. After conducting the public discussion and listening to the student’s defense, the thesis was accepted. The thesis was summarized as follows:
One of the primary sources of water contamination is oil spills. As a result of the critical importance of crude oil in modern industrial society, oil spills, specifically those involving crude oil, generate substantial environmental and ecological difficulties. Nanotechnology has demonstrated its efficacy in remedying oil spills. In this context, a research has been conducted to examine the crude oil spill cleanup using different magnetic nanoparticles (MNPs) as adsorbents.
The first part of this study focused on the preparation of three different MNPs (Spinel Ferrite and Iron oxides). Magnetite (Fe3O4), Zinc Ferrite (ZnFe2O4) (ZFO), and Maghemite (γ-Fe2O3) MNPs were properly prepared by co-precipitation, Sol gel, and homogeneous co-precipitation methods, respectively. MNPs have been characterized by means of Fourier transform infrared Spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), transmission electron microscopy (TEM), surface area using the Brunauer-Emmett-Teller (BET), and scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM).
The MNPs successful synthesis was revealed by XRD, and the crystallite sizes were 12.5, 10.8, and 11.1nm for ZFO, Magnetite, and Maghemite, respectively. The AFM reports confirmed that the prepared MNPs were all nanosized material with average particle sizes of 90.55, 37.7, and 30.6 nm for ZFO, Magnetite, and Maghemite.
Iron oxides (Magnetite and Maghemite) were coated with ethylenediaminetetraacetate (EDTA) to obtain EDTA-Magnetite and EDTA-Maghemite MNPs, which were applied for the first time as an adsorbent for oil spill from the water surface. Coated MNPs were characterized by an AFM, which proved that the EDTA coated MNPs remained within nanoscale dimensions with the mean diameter of the particles of about 78.9 and 100.5nm for EDTA-Magnetite and EDTA-Maghemite. FTIR confirmed the bonding of functional groups from EDTA to the iron oxide surfaces, and BET verified that the EDTA improved the MNPS surface areas to be 97.64 and 102.59 m2/g for EDTA-Magnetite and EDTA-Maghemite.
The second part was a batch study to test the prepared adsorbents using Iraqi crude oil with different APIs (23, 28.4, 40.3). Removal experiments were carried out using the gravimetric oil removal method at room temperature with a mass range of adsorbent (0.02-0.06 g), initial oil concentration (5 – 45 g/L), and contact time (2- 10 min.). A neodymium magnet was utilized to extract the oil-contaminated magnetic nanoparticles from the water. The results at optimum operation conditions (dose = 0.02g, contact time = 8min., and initial oil concentration = 25g/L) demonstrated that the oil with the lowest API (23) had the highest gravimetric oil removal (GOR g/g) values of around 22.9, 21.7, and 17.8 g/g for EDTA-Maghemite, EDTA-Magnetite, and ZFO, respectively. Contrastingly, the samples with the highest API values (28.4 and 40.3) had a lower GOR of 19.75, 18.8, and 16.13 g/g (API 28), and 11.77, 10.9, and 7.9 g/g (API 40). The isotherm equilibrium data for the three prepared adsorbents show that the Langmuir model fits the experimental results of crude oil removal, while the kinetic model that accurately characterized The experimental data was pseudo-second-order.
The research revealed that EDTA-Maghemite MNPs was the more efficient adsorbent for oil spill from water surface.
