Abstract: Furfural was used as extraction solvent to remove the polycyclic aromatics (PCA) from the coal-based hydrocracking tail oil. The effect of extraction temperature, ratio of solvent to oil and extraction stages on the yield and the removal rate of PCA in raffinate oil was investigated. With single-stage extraction process, increasing the extraction temperature or the ratio of the solvent to feed resulted in reduction of the raffinate yield and increase of the removal rate of PCA. The removal rates of PCA of the raffinate were both more than 72.0% and the yields of the raffinate were both more than 70.0% in two-stage and three-stage counter-current extraction processes. Meanwhile, the raffinate oil still had high content of unextracted monocyclic and bicyclic aromatics and the aromatic carbon rate CA was greater than 10.0%, which is conducive to the production of co-friendly coal-based rubber oils.

Key words: solvent extraction, hydrocracking tail oil, polycyclic aromatics, furfural