METHOD OF SELECTIVELY PURIFYING LUBE OIL FRACTIONS Russian patent published in 1998 - IPC

FIELD: petroleum processing and chemical engineering. SUBSTANCE: invention, in particular, relates to liquid-phase extraction of lube oil fractions by various solvents, such as phenol, furfural, 2-methylpyrrolydone, etc. Raw material is introduced into medial part of extractor and solvent into its top part in presence of counter-solvent fed into bottom part of extractor. Solvent from raffinate and extract solutions is further recovered to yield raffinate and extract. A part of extract is cooled to temperature not exceeding raw material inlet temperature and is introduced into lower part of extractor above counter-solvent introduction point. A part of raffinate is also cooled to temperature not exceeding raw material inlet temperature and introduced into lower part of extractor between raw material and extract introduction points. EFFECT: increased yield of phenol raffinate. 2 dwg , 9 tbl