A liquid-liquid distribution method for the study of complexation of cadmium in natural waters

Liquid-liquid distribution of cadmium between pyridine solution in benzene and aqueous phase containing iodide has been radiometrically investigated, in order to develop a simple method for the study of complexation of cadmium in aqueous solutions. The degree of complexation of cadmium can be determined from the decrease of the distribution ratio in the presence of complexing agents forming non-extractable complexes with this metal. The method was verified for the determination of the composition and stability constants of cadmium with acetate, tartrate, oxalate and glycolate anions and applied for the study of complexation of cadmium in natural waters.