A Simple Scheme for Extraction of Asphaltenes from Asphalt at Room Temperature

This paper proposes a simple scheme to separate asphaltenes from asphalt at room temperature without heating or refluxing. The proposed scheme can solve the problems of high energy cost, expensive devices, and safety risks of flammable steam in standard methods of asphaltene extraction. First, the asphalt is dissolved in a good solvent to obtain a solution containing asphaltenes, and the inorganic impurity as well as residual carbons are removed by filtration. Then, the solution containing asphaltenes is dropped into poor solvent to let asphaltenes flocculate into suspended solids. Finally, the suspension is filtered, and the filter cake is dried to obtain asphaltene solid. The CHNS elements and 1H-Nuclear magnetic resonance were characterized for the obtained product. Compared with asphalt, the C/H element ratios and the aromatic carbon ratios of the product were higher, which matched the elemental and structural characteristics of asphaltenes. The asphaltene yields obtained from different solvents were compared, and the reasons for the yield differences were analyzed. Recovered solvent could be used to extract asphaltenes, and the yield was found to decrease with the extraction times.