COMBINATION OF EXTRACTIVE DISTILLATION AND LIQUID EXTRACTION PROCESS FOR SEPARATION OF A HYDROCARBON FEED MIXTURE

摘要

An extractive distillation zone is used in combination with a liquid phase extraction zone to provide relatively highly aromatic heavy and light extracts and a relatively aromatic-free raffinate stream. The process allows a feed mixture which contains raffinate materials in at least two fractions of aromatics to contact an extractive distillation zone in which solvent passed thereinto dissolves the heavy aromatics from the feed stock. The overhead vapors from the extractive distillation zone are condensed and passed into a liquid phase extraction zone where the light aromatic fraction of the feed stock is extracted and substantially separated from the non-aromatic raffinate components. The raffinate, light extract and heavy extract materials are separately recovered. The process is applicable to most hydrocarbon separations and in particular can be used in the petrochemical industry to separate close boiling aromatic and non-aromatic materials.