Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6310488 | Chemosphere | 2013 | 7 Pages |
Abstract
The molecular scale sorption, diffusion and distribution of asphaltene, resin, aromatic and saturate fractions of heavy crude oil on quartz surface were studied using molecular dynamic simulation. Sorption of saturates on quartz decreased by 31% when temperature increased from 298 to 398Â K while opposite trend was observed for resins, but insignificant changes were found in asphaltenes and aromatics. Despite of this variety, the main contribution of interactions was van der Waals energy (>90%) irrespective of molecular components and temperatures. The diffusion coefficient of saturates was predicted as 10.8Â ÃÂ 10â10Â m2Â sâ1 while that of the remaining fractions was about 4Â ÃÂ 10â10Â m2Â sâ1 at 298Â K. The most likely oil distribution on quartz surface was that aromatics and saturates transported randomly into and out of the complex consisting of asphaltenes surrounded by resins, which was influenced by temperature. Overall, the knowledge on quartz-oil and oil-oil interactions gained in this study is essential for future risk assessment and remediation activities as previous studies on soil remediation either limited to light oil fractions with <40 carbons or treated the heavy crude oil as a single pseudo entity ignoring the interactions between oil fractions.
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Authors
Guozhong Wu, Lin He, Daoyi Chen,