AROMATIC DINITRILES ARE CONVERTED TO THE CORRESPONDING DIACIDES BY A PROCESS WHICH COMPRISES HYDROLYZING THE DINITRILE IN THE PRESENCE OF AN ALKALI METAL BICARBONATE, REMOVING THE AMMONIA AND CARBON DIOXIDE FROM THE HYDROLYZATE DIOXIDE TO FORM A PRECIPITATE OF THE ALKALI METAL CARBON DIOXIDE TO FORM A PRECIPITATE OF THE ALKALI METAL MONOSALTS OF THE DIACIDE AND A MOTHER LIQUOR CONTAINING THE DIACID SALTS AND ALKALI METAL BICARBONATE, SEPARATING THE PRECIPITATE FROM THE MOTHER LIQUOR, RECYCLING THE MOTHER LIQUOR TO THE HYDROLYSIS STEPS, DISPROPORTIONATING THE PRECIPITATE TO FORM FREE DIACIDE AND ALKALI METAL DISALT OF THE DIACID, SEPARATING THE DIACID FROM THE DISALT, RECYCLING THE DISALT, AND RECOVERING THE DIACID.