Patent ID: 7884232

Claim:
A process for producing terephthalic acid, said process comprising: (a) introducing an aggregate solvent feed, comprising (i) recycled solvent feed and (ii 0 isophthalic acid (IPA), into at least one oxidation reactor wherein IPA is present in the aggregate solvent feed in an amount ranging from 40 to 1200 ppmw; (b) oxidizing an oxidizable compound in a liquid phase of a multi-phase reaction medium contained in a reaction zone of said oxidation reactor, wherein said oxidizing causes at least 10 weight percent of said oxidizable compound to form solids in said reaction medium; and (c) withdrawing a slurry comprising a liquid mother liquor and solid crude terephthalic acid (CTA) particles from said reaction zone, wherein a representative sample of said CTA particles contains 2,7-dicarboxyfluorenone (2,7-DCF), wherein said 2,7-DCF is present in said representative sample, and wherein the amount present is up to and less than 5 ppmw.