PROCESS FOR THE PURIFICATION OF POLYCARBOXYLIC AROMATIC ACIDS

摘要

A process for improving the purity of an aromatic polycarboxylic acid by reducing the content of metal ions in the aromatic polycarboxylic acid and/or removing organic impurities from the aromatic polycarboxylic acid, comprising transforming the acid into the corresponding amine or ammonium salt in an aqueous solution, and then acidifying the solution so obtained with a strong acid, to precipitate the purified aromatic polycarboxylic acid.