Abstract: A process for the separation of palladium from solvent-free at room temperature solid crude reaction mixtures comprising aryl acetic acids of the general formula (I), wherein Z means phenyl, napht-2-yl, 9H-fluoren-2-yl, substituted carbazol-2-yl, benzoxazol-5-yl, either of which can be substituted with H, C1-C8-alkyl optionally cyclic and optionally substituted with —F or —Cl, C6-C10-aryl optionally substituted with F or Cl OR4, COR5, F, —Cl; optionally substituted pyrrolyl or dehydropyrrolyl or 1-oxo-1,3-dehydro-isoindol 2-yl; R1 means H or C1-C4-alkyl; R2, R3, R4, R5 mean independently of each other H, C1-C8 alkyl, C6-C10-aryl optionally substituted with —F or Cl, or thiophenyl; which crude mixture is obtained by palladium catalyzed carbonylation, by adsorption of the palladium on solid adsorbents, characterized in that the adsorption is carried out in the absence of a reducing agent for palladium and at a temperature, where the crude reaction mixture is molten.