Patent ID: 7546747

Claim:
A process for producing a dried carboxylic acid cake, said process comprising: (a) oxidizing in an oxidation zone an aromatic feedstock to produce a carboxylic acid slurry; (b) removing in a liquor exchange zone impurities from said carboxylic acid slurry to form a water-wet carboxylic acid cake, a mother liquor stream, a solvent mother liquor stream, and a solvent/water byproduct liquor stream; wherein at least one solvent is, added counter current to the flow of said carboxylic acid slurry; wherein said liquor exchange zone comprises one solid-liquid separation device capable of performing the removal of said impurities from said carboxylic acid slurry and producing said water-wet carboxylic acid cake from said carboxylic acid slurry; wherein said solvent comprises acetic acid, and (c) drying said water-wet carboxylic acid cake in a drying zone to form said dried carboxylic acid cake; wherein said water-wet cake maintains the form of a cake between step (b) and (c).