Extraction process for removal of impurities from mother liquor in the synthesis of carboxylic acid

A process comprising the following steps:

• (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 about 85 wt % to about 99 wt % of said solvent and water is removed from said mother liquor in step (a) and step (b) combined;
• (c) separating organic impurities with a water-solvent solution from said super concentrated mother liquor stream in a solid-liquid separation zone to form an aqueous stream and a second aqueous stream;
• wherein said water-solvent solution is added to said solid liquid separation zone at a temperature range of about 20° C. to about 70° C.;
• (d) mixing in a mixing zone water and optionally an extraction solvent with said aqueous stream and said second aqueous stream to form an aqueous mixture;
• (e) adding an extraction solvent to said aqueous mixture in an extraction zone to form an extract stream and a raffinate stream;
• and
• (f) optionally separating said extract stream in a separation zone to form a high boiling point organic impurities stream and a recovered extraction solvent stream.