Asphaltene Particle Size Distribution Studies by Fractals
The solubilities of three different asphalt colloidal types (sol, sol-gel, and gel) were determined in various solvents. Asphalt cannot completely dissolve in the solvent, and therefore forms a colloidal system. An unknown number of hydrocarbon particles of different particle size are dispersed in this solution. Korčák distribution has been proposed previously to estimate the size distribution of islands in ocean archipelagos using the concept of fractals; it was employed in this work as an attempt to estimate the size distribution of asphalts. From Korčák distribution, we derived an additional equation to determine the size distribution and particle irregularity in the asphalt colloidal solution. From the relationship between the solvent molecule size and the mass of asphalt precipitated per molar solvent in various solvents, size distribution and irregularity could be obtained by the derived Korčák distribution. It was found that the value of size distribution for the three different colloidal asphalts is different, and it can be used to indicate sol, solgel, and gel types of asphalt. In this particular study, however, the values of irregularity were random among the samples, and therefore failed to be a tool to differentiate the three colloidal types.
KeywordsColloidal System Heavy Hydrocarbon Asphaltene Precipitation West Texas Intermediate Asphalt Sample
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