Recovery of aromatics

Claim 1

AN ABSORPTION, STRIPPING, EXTRACTION PROCESS FOR RECOVERING AROMATIC HYDROCARBONS FROM A HYDROCARBON MIXTURE CONTAINING AROMATIC AND NON-AROMATIC HYDROCARBONS OF WHICH THE AROMATIC CONTENT IS AT LEAST 75% BY WEIGHT OF SAID MIXTURE WHICH COMPRISES INTRODUCING A SULFOLANE SOLVENT INTO AN EXTRACTIVE ABSORBER STRIPPING ZONE NEAR THE TOP OF THE ZONE, INTRODUCING THE HIGHLY AROMATIC FEED MIXTURE INTO THE ZONE AT A POINT BELOW THE INTRODUCTION OF THE SULFOLANE SOLVENT, COUNTERCURRENTLY CONTACTING THE VAPOR OF SAID MIXTURE WITH THE LIQUID SULFOLANE SOLVENT TO SELECTIVELY ABSORB THE AROMATIC COMPONENTS OF THE VAPOR AT HIGH PURITY, WITHDRAWING OVERHEAD FROM SAID ZONE, A VAPOR-PHASE RAFFINATE CONTAINING NON-AROMATIC HYDROCARBONS, SULFOLANE SOLVENT AND SOME AROMATIC HYDROCARBONS, CONDENSING SAID RAFFINATE AND EXTRACTING THE RAFFINATE IN A RAFFINATE EXTRACTION ZONE WITH A LEAN SULFOLANE SOLVENT TO PRODUCE AT FAT SULFOLANE SOLVENT AND A PURE NONAROMATIC HYDROCARBON RAFFINATE AND INTRODUCING THE FAT SULFOLANE SOLVENT FROM THE RAFFINATE EXTRACTION ZONE INTO A SOLVENT STRIPPING ZONE, WITHDRAWING FROM THE BOTTOM OF THE EXTRACTIVE ABSORBER STRIPPER ZONE, THE FAT SULFOLANE SOLVENT CONTAINING THE SELECTIVELY ABSORBED AROMATICS INTRODUCING THE FAT SULFOLANE SOLVENT INTO THE SOLVENT STRIPPING ZONE ALONG WITH THE FAT SOLVENT FROM THE RAFFINATE EXTRACTION ZONE, STRIPPING THE EXTRACT THEREFROM AND RETURNING THE LEAN SOLVENT TO THE EXTRACTIVE ABSORBER-STRIPPER ZONE AT A POINT ABOVE THE FEED ENTRY AND TO THE RAFFINATE EXTRACTION ZONE.