Summary: | Reducing the aromatics entrainment during coal-based liquids dephenolization has been investigated by deep eutectic solvents (DESs) as designed. Results showed that aromatics with a chain alkyl group were more easily entrained and phenolic compounds promoted the transfer of aromatics from oil to DESs. Among the DESs investigated, ChCl–glycerol was the best for separation of phenolic compounds from coal-based liquids, having a lower aromatics entrainment. Although adding H2O to ChCl–glycerol reduced the aromatics entrainment, simultaneously suppressed the phenol removal efficiency. A narrow boiling range of phenol oil fraction was benefit for phenols extraction with lower aromatics entrainment. The O–H…π and C–H…π among aromatics and phenolic compounds and/or DESs contributed for the aromatics entrainment, and compounds with specific structures were bound to be entrained.
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