An Experimental Investigation and Modeling of Asphaltene Adsorption Kinetics on Synthesized Iron Oxide Nanoparticles

Nanotechnology is of significant importance in many scientific fields. In view of engineering problems, nanomaterials have found wide practical applications. In this work, iron oxide nanoparticles called maghemite (γ-Fe2O3) were synthesized. The synthesized nanoparticles were used to adsorb asphaltene from prepared asphaltene-toluene solutions. Asphaltene adsorption kinetic behavior was modeled using experimental data. For the synthesis of maghemite nanoparticles, the co-precipitation of ferric and ferrous ions method as a simple and inexpensive method was selected. The crystalline structure and morphology of synthesized maghemite was investigated using X-ray diffraction (XRD) and scanning electron microscope (SEM) respectively. The nanoparticles were also characterized by using FT-IR spectrum. The results of these analyses showed that the γ-Fe2O3 nanoparticles had a crystalline structure with a size smaller than 50 nm and were spherical in shape. The maghemite nanoparticles were used for the adsorption of asphaltenes. The results obtained from adsorption kinetics analysis showed that asphaltene was rapidly adsorbed onto γ-Fe2O3 nanoparticles, and equilibrium was achieved in less than 2 hrs. The Lagergren pseudo-first-order and the pseudo-second-order models were employed for determination of the adsorption kinetics. It was found that the kinetic results were in good agreement with the pseudo-second-order model.