Patent ID: 7381386
Filing Date: 2008-06-03
Classification: C07C,Y02P

Abstract:
1. A process comprising: (a) evaporating a mother liquor comprising a carboxylic acid, a metal catalyst, impurities, water and a solvent in a first evaporator zone to produce a vapor stream and a concentrated mother liquor stream; (b) evaporating said concentrated mother liquor stream in a second evaporator zone to form a solvent rich stream and a super concentrated mother liquor stream; wherein said super concentrated mother liquor stream is a high temperature molten dispersion; wherein said evaporating in said second evaporator zone is conducted at a temperature from about 150° C. to about 220° C.; (c) mixing in a mixing zone a water-solvent solution and optionally an extraction solvent with said super concentrated mother liquor stream to form an aqueous mixture; (d) adding an extraction solvent to said aqueous mixture in an extraction zone to form an extract stream and a raffinate stream; and (e) separating said extract stream and said solvent rich stream in a separation zone to form a high boiling point organic impurities stream and a recovered extraction solvent stream.