Sorption of Asphaltenes onto Nanoparticles of Nickel Oxide Supported on Nanoparticulated Silica Gel

The aim of this study is to analyze the effect of temperature and NiO content on the asphaltene uptake by a hybrid nanomaterial composed of nickel oxide nanoparticles supported on a nanoparticulated matrix of silica gel. The silica gel nanoparticles were synthesized by sol-gel method. The silica-supported nanomaterial was prepared by an incipient wetness technique. At constant temperature, adsorption of asphaltenes onto the hybrid nanomaterials increased with increasing its nickel oxide content. Regardless of the asphaltene concentration, asphaltene uptake by the hybrid nanomaterials decreased with increasing temperature. Experimental data on asphaltene sorption isotherms were adequately adjusted by the Freundlich model. The calculated thermodynamic properties for the sorption of asphaltenes onto the nanoparticulated-materials confirmed the spontaneity and exothermic nature of this process.