1. Selective extraction of aromatics from residual oil with subcritical water.
- Author
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Zhu, Meng-Han, Liu, Yin-Dong, Wang, Li-Tao, Huang, Zi-Bin, and Yuan, Pei-Qing
- Subjects
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VAN der Waals clusters , *QUASIMOLECULES , *HEAVY oil , *AROMATIC compounds - Abstract
Based on theoretical calculations and experimental characterizations, the extraction of heavy oil components using subcritical water (Sub-CW) as an extraction solvent was studied in the temperature range of 250–325 °C. According to theoretical calculations, small-scale polycyclic aromatic hydrocarbons (PAHs) are preferentially dissolved in Sub-CW. Meanwhile, the dissolution of heavy oil molecules with large-scale aromatic structures and heterocyclic rings in Sub-CW is hindered. The increase in temperature reduces the hydrogen bonding force between water molecules and the van der Waals repulsion between Sub-CW and PAHs, promoting the dissolution of PAHs in Sub-CW. Extraction experiments applied in a semi-continuous device confirm that Sub-CW selectively extracts aromatic hydrocarbons from heavy oil. Increasing extraction temperature increases the yield of the extract. The aromatic hydrocarbon content in the extract at 325 °C reaches 80 wt%, which is 27 wt% higher than feedstock value. In addition, the asphaltene content in the extract is reduced from the feedstock value of 14 wt% to 2 wt%. • Sub-CW was used as a property-tunable solvent for extracting heavy oil components. • Sub-CW selectively extracts aromatic hydrocarbons from heavy oil. • The yield and composition of the extract are sensitive to extraction temperature. • Opposite distribution of HSP hinders dissolution of PAHs/hetero-PAHs in Sub-CW. • Destruction of hydrogen bonds promotes dissolution of PAHs/hetero-PAHs in Sub-CW. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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