Methods for purifying a carboxu00eclico acid from a mixture, to recover the purified terephthalic acid from the effluent of a process for the production of terephthalic acid and 4 - carboxibenzaldeu00ecdo to oxidize and / or 3 - carboxibenzaldeu00ecdo

摘要

Methods for purifying a carboxu00eclico acid from a mixture, to recover the purified terephthalic acid from the effluent of a process for the production of terephthalic acid and 4 - carboxibenzaldeu00ecdo to oxidize and / or 3 - carboxibenzaldeu00ecdo. A method and apparatus for purifying carboxylic acids are disclosed.A mixture containing crude carboxylic acid is contacted with a selective solvent of crystallization to form a slurry of a complex salt of the carboxylic acid and the solvent of crystallization selective. The complex salt is recovered and optionally processed to recover the carboxylic acid free.The method and the device of the invention are particularly suitable for purifying aromatic dicarboxylic acids such as acid tereflu00e1lico. The present invention also reduces contamination by isomers of carboxibenzaldeu00eddo acids by oxidizing ftu00e1licos gross is the carboxibenzaldeu00eddo corresponding to phthalic acid.