Process for separating aromatic hydrocarbons from mixtures containingthem by liquid-liquid extraction and azeotropic distillation

Abstract

Abstract AROMATIC HYDROCARBONS ARE SEPARATED FROM A MIXTURE OF LIQUID HYDROCARBONS. THE MIXTURE OF LIQUID HYDROCARBONS IS EXTRACTED IN THE LIQUID PHASE IN AN EXTRACTION ZONE AT A TEMPERATURE OF ABOUT 40*C. TO ABOUT 80*C. WITH ETHYLENEDIAMINE SOLVENT HAVING A WATER CONTENT OF FROM 0% TO 2/% BY WEIGHT TO FORM AN EXTRACTED PHASE AND A RAFFINATE PHASE. THE EXTRACTED PHASE COMPRISES PREDOMINANTLY AROMATIC HYDROCARBONS, SOLVENT, AND A MINOR AMOUNT OF NON-AROMATIC HYDROCARBONS. THE RAFFINATE PHASE COMPRISES PREDOMINANTLY NON-AROMATIC HYDROCARBONS. THE EXTRACTED PHASE AND THE RAFFINATE PHASE ARE SEPARATELY COLLECTED. THE EXTRACTED PHASE IS COOLED TO A TEMPERATURE AT LEAST 30*C. LOWER THAN THE TEMPERATURE OF THE EXTRACTION. THE COOLED EXTRACTED PHASE IS THEN SEPARATED INTO A HEAVIER SOLVET CONTAINING PHASE, AND A LIGHTER HYDROCARBONS CONTAINING PHASE WHICH IS SCRUBBED WITH WATER TO OBTAIN AN AQUEOUS ETHYLENEDIAMINE CONTAINING PHASE AND A HYDROCARBONS PHASE. THE HYDROCARBONS PHASE IS AZEOTROPICALLY DISTILLED TO OBTAIN AN OVERHEAD PRODUCT COMPRISING NON-AROMATIC HYDROCARBONS, AND A BOTTOM PRODUCT CONSISTING ESSENTIALLY OF AROMATIC HYDROCARBONS WHICH ARE SUBSEQUENTLY RECTIFIED.

Inventors

• 👤 F Barilli
• 👤 L Lugo
• 👤 Fiore L Di
• 👤 C Reni

Bibliographic Details