METHOD OF OILY FRACTION SELECTIVE REFINING Russian patent published in 1998 - IPC

FIELD: chemical technology. SUBSTANCE: method involves countercurrent contact of raw feeding to middle zone of extractor with solvent feeding to upper zone of extractor in the presence of antisolvent feeding to bottom zone of extractor followed by solvent regeneration from rafinate and extractive solutions and rafinate and extract producing. Part of rafinate is recovered to bottom zone of extractor (but not above of zone of raw feeding) at temperature not exceeding of that of raw feeding and not lower of that of antisolvent feeding. Part of extract is recovered in extractor between solvent and rafinate feeding at temperature not exceeding of that of solvent feeding and not lower of that of antisolvent feeding. EFFECT: increased rafinate yield in process of liquid extraction. 2 dwg, 9 tbl