文摘
Asphaltenes exhibit an amphiphlic behavior and tend to form colloidal i-mers, because of their chemical structure. The formation of colloidal aggregates can generate formation damage for the precipitation and/or deposition of asphaltenes, because of the degree of self-association, altering the wettability of rock surface and significantly affect crude oil viscosity and specific gravity. This study aims at introducing a novel model for describing, at the macroscopic level, the adsorption equilibria of self-associating molecules such as asphaltenes in solution onto solid surfaces based on the 鈥渃hemical theory鈥? The model describes the adsorption isotherms temperature-dependent using three parameters, namely, maximum amount adsorbed, constant of i-mer reactions, and Henry鈥檚 law constant. Furthermore, a temperature-independent model of five parameters, based on the modifications of the constants of reaction and Henry鈥檚 law using an Arrhenius-type equation was proposed for estimating the thermodynamics parameters, such as 螖Gads掳, 螖Hads掳, and 螖Sads掳 of the adsorption process. This model improves the understanding of interactions asphaltene鈥揳sphaltene and asphaltene鈥搒olid surface on the adsorption鈥揺quilibrium process. The theoretical predictions of isotherms were validated successfully by determining the root mean-square errors (RSM%) between data obtained from published literature and values predicted for asphaltenes and surfaces with differing chemical natures. More than 40 experimental data taken from literature have been used for validating the solid鈥搇iquid equilibrium (SLE) model for describing the adsorption isotherm of asphaltenes from different origins on surfaces with different chemical nature, which shows the model robustness due to the complexity of the liquid phase adsorption for those complex molecules.