Process for the separation of phthalic acid and phthalic anhydride in a process for the cyclisation of ortho-benzoylbenzoic acid

摘要

Process for the separation of phthalic acid and phthalic anhydride from ortho-benzoylbenzoic acid by heating these products and ortho-benzoylbenzoic acid containing them at a temperature between 200 DEG C and 250 DEG C in the presence of a superactive bleaching earth in a process for the cyclisation of ortho-benzoylbenzoic acid in the presence of the same superactive bleaching earth.