PURIFICATION AND RECOVERY OF METHYL ETHYL KETONE

PURPOSE:To efficiently purify methyl ethyl ketone, by using caustic soda for extracting and separating water in an zeotropic liquid and a solution of caustic soda containing extracted water for decomposing and removing impurities in purifying and recovering the titled compound in an active carbon adsorption type solvent recovery apparatus. CONSTITUTION:Air containing methyl ethyl ketone (MEK) is fed into an adsorption vessel 2-1 or 2-2 to adsorb the MEK on active carbon 3-1 or 3-2. The MEK adsorbed on the active carbon is desorbed with steam and fed with steam to a flash tank 4. In the tank 4, an aqueous solution of caustic soda from a separator 11 and MEK vapor are subjected to gas-liquid contact to decompose and remove impurities. Vapor from the tank 4 is cooled and condensed in a condenser 5 and separated by specific gravity in a separator 6. The MEK is fed to a distillation column 9 to take out moisture in the MEK together with MEK of azeotropic composition from the column top. The moisture and MEK of azeotropic composition are cooled and condensed in a reflux condenser 10, fed to the separator 11 to extract water with the caustic soda solution and the dehydrated MEK is refluxed to the distillation column 9.