Process for drying methyl ethyl ketone

Claim 1

IN A PROCESS FOR OBTAINING SUBSTANTIALLY ANHYDROUS METHYL ETHYL KETONE FROM AN AQUEOUS MIXTURE THEREOF, TOGETHER WITH WATER-SOLUBLE IMPURITIES, THE STEPS WHICH COMPRISES SUBJECTING SAID AQUEOUS MIXTURE TO EXTRACTIVE DISTILLATION WITH WATER IN A FRACTIONATING COLUMN TO OBTAIN A DISTILLATE CONSISTING ESSENTIALLY OF THE METHYL ETHYL KETONE-WATER BINARY AZEOTROPE AND WATER-SOLUBLE IMPURITIES, INTRODUCING SAID DISTILLATE INTO AN EXTRACTION ZONE, INTRODUCING A C6 HYDROCARBON INTO SAID ZONE COUNTERCURRENTLY TO THE FLOW OF SAID DISTILLATE TO OBTAIN A HYDROCARBON EXTRACT AND AN AQUEOUS RAFFINATE LAYER, INTRODUCING WATER AT A LELVEL IN SAID ZONE ABOVE THE POINT OF INTRUDUCTION OF SAID DISTILLATE WHEREBY SAID WATER-SOLUBLE IMPURITIES PRESENT IN SAID HYDROCARBON EXTRACT ARE SUBSTANTIALLY COMPLETELY REMOVED THEREFROM, SUBJECTING THE RESULTING WASHED HYDROCARBON EXTRACT TO DISTILLATION TO OBTAIN AS BOTTOMS SUBSTANTIALLY ANHYDROUS METYL ETHYL KETONE, REMOVING OVERHEAD A TERNARY AZEOTROPE OF WATER, METHYL ETHYL KETONE AND C6 HYDROCARBON, ALLOWING THE RESULTING OVERHEAD TO SEPARATE INTO AN ORGANIC LAYER AND A WATER LAYER, COMBINING SAID WATER LAYER WITH SAID RAFFINATE LAYER AND RETURNING THESE COMBINED STREAMS TO SAID FRACTIONATING COLUMN.