Experimental and modeling studies of the effects of different nanoparticles on asphaltene adsorption

Adsorption experiments for three commercial metal oxide nanoparticles (SiO₂, Al₂O₃, and MgO) were carried out to examine the effect of each nanoparticle on asphaltene inhibition. The results are reported on the basis of adsorption per mass of adsorbent. The adsorption data were used in four isotherm adsorption models (Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich models) for better understanding of adsorption mechanisms. Among the models, Dubinin-Radushkevich produced better prediction. According to the obtained data, the adsorption affinity toward asphaltene was in the following order: SiO₂ > MgO > Al₂O₃. Influence of the main factors such as surface chemistry and specific surface area shows significant effect on the amount of adsorption. It was found that the multilayer adsorption and physisorption mechanism plays an important role in asphaltene adsorption, which was confirmed by Freundlich, Temkin, and Dubinin-Radushkevich models.