Experimental Investigation of Mechanisms of Asphaltene Aggregation in Toluene and n-Heptane Mixtures

The nature of aggregation kinetics of colloidal asphaltene particles in mixture of toluene and n-heptane was investigated by utilizing a microscope with appropriate magnification. The concentration of asphaltenes in toluene varied from 1g/l to 6 g/1. The theoretical model developed employs Smoluchowski fundamental approach. There are two main mechanisms associated with aggregation process. These mechanisms are diffusion limited aggregation (DLA) and reaction limited aggregation (RLA). At the asphaltene concentrations below the critical micelle concentration (CMC), the DLA mechanism is dominant, while at concentrations above the CMC, at the initial stage of aggregation process the RLA mechanism is observed and then the mechanism tends to DLA

کلیدواژه ها:

CMC ، Classic DLVO Theory ، DLA & RLA Mechanisms ، Fractal Dimension