1.Commercial cadmium carbonate, without any prior treatment, can be used as a catalyst for the ketonization of dicarboxylic acids to cyclic ketones. On the examples of the ketonization of adipic, suberic, and 3,3,6,6-tetramethylsuberic acids it was shown that high yields of the ketones can be obtained when operating with CdCO3and using charges of the acid ranging from 0.5 to 150 g.2.Two methods for carrying out the ketonization were evaluated. The relative efficiency of the methods is importantly dependent on the nature of the acid.