Verfahren zur kontinuierlichen Herstellung von aromatischen Carbonsaeuren oder deren Anhydriden

摘要

In a process for the liquid phase oxidation of alkylaromatic compounds to aromatic carboxylic acids in presence of covalent halides or salts of heavy metals, the liquid phase is cycled countercurrently to oxygen through successive reactors maintained at identical pressure, with no condensation of vapours between reactors, no fresh solvent being added to the final reactor and the recovered mother-liquors being continuously recycled. Examples describe the production of tere-, iso- and orthophthalic acids (and phthalic anhydride) from the corresponding xylenes.ALSO:A catalyst for oxidising alkylaromatic compounds to aromatic carboxylic acids comprises equimolecular amounts of (hydrated) BaBr2, MnCl2 and Co(OAc)2.