Kinetic and thermodynamic equilibrium of asphaltenes sorption onto nanoparticles of nickel oxide supported on nanoparticulated alumina

• Published in: Fuel (Guildford) 2013-03, Vol.105, p.408-414
• Main Authors: Franco, Camilo, Patiño, Edgar, Benjumea, Pedro, Ruiz, Marco A., Cortés, Farid B.
• Format: Article
• Language: English
• Subjects: Aluminum oxide; Applied sciences; Asphaltene; Asphaltenes; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fuels; Hybrid nanomaterials; Nano-alumina support; Nanocomposites; Nanomaterials; Nanoparticles; Nanostructure; Nickel oxides; Sorption; Sorption equilibrium; Sorption kinetic
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2012.06.022

► Nanoparticles of nickel oxide supported on a nanoparticulated matrix of alumina (SHS) were prepared. ► Adsorption affinity increased with increasing the NiO content on the alumina surface. ► Alumina-SHS nanomaterials can be used as excellent adsorbents for light and heavy oil upgrading. ► Complete asphaltenes sorption on Alumina-SHS can be achieved rapidly around 2min. ► The asphaltenes sorption processes were analyzed in terms of isotherm, kinetics, and thermodynamics models. Nanoparticles can be used as adsorbents and catalyst in oil industry for in situ upgrading in the oil industry. The main objective of this study was to investigate the kinetic and thermodynamic equilibrium of asphaltene sorption onto nanoparticles of nickel oxide supported on nanoparticulated alumina at different temperatures, times, and concentrations. Alumina-supported nanoparticles were characterized by N2 adsorption at −196°C and X-ray diffraction. Complete asphaltene sorption on nanoparticles of nickel oxide supported on nanoparticulated alumina can be effectively reached at relatively short times (around 2min), making this sorbent a good candidate for asphaltene sorption. The sorption equilibrium of asphaltene for alumina and alumina-supported nanoparticles at different temperatures (25, 40, 55, and 70°C) over a wide range of asphaltene concentration, from 150 to 2000mg/L, was determined using a static method. The Langmuir and Freundlich models were used for correlating the experimental data of the sorption equilibrium at different temperatures. Regarding to the Al and AlNi5 samples, the experimental data on asphaltene sorption isotherms were adequately adjusted by the Freundlich model. On the other hand, for the AlNi15 sample the experimental data were adequately fitted by the Langmuir model. The adsorption of asphaltene on NiO supported on alumina was much higher than that over alumina for the range of equilibrium concentrations tested. Pseudo-first-order and pseudo-second-order kinetic models were applied to the experimental data obtained at different concentrations of asphaltenes from 250 to 2000mg/L for alumina and alumina-supported materials, with a better fitting to the pseudo-second-order model.