METHOD FOR PRODUCING PHTHALIC ANHYDRIDE FROM REACTION GASES

摘要

The invention relates to a method for the partial fractional desublimation of phthalic anhydride from reaction gases and subsequent processing to give pure phthalic anhydride by distillation with integrated phthalic acid cleavage and recirculation of the phthalic anhydride so obtained to the desublimation stage.