Patent ID: 7462736

Claim:
A process for producing purified terephthalic acid (PTA), said process comprising: (a) oxidizing an aromatic compound in an oxidation zone to thereby produce a crude slurry comprising crude terephthalic acid (CTA) particles; (b) subjecting at least a portion of said crude slurry to purification to thereby produce a purified slurry comprising PTA particles, oxidation byproducts, and an aliphatic acid in an amount of at least about 10 weight percent; and (c) isolating at least a portion of said PTA particles from said purified slurry in a product isolation zone to thereby produce a PTA product, wherein said product isolation zone is defined within a rotary pressure drum filter, wherein the cumulative rate at which said oxidation byproducts exit said PTA production process with said PTA product and/or are combined with said PTA product downstream of said PTA production process is at least about 15 percent of the net make rate of said oxidation byproducts in said PTA production process.