Atomic absorption determination of cadmium in natural waters after concentration with capric acid and amines

A study was carried out of the extraction of cadmium by a 1 M solution of capric acid in heptane in the presence and absence of pyridine, benzylamine, and 1,10-phenanthroline. The stoichiometric ratio of the components in the extracted complexes, and the degree of their polymerization in heptane, were established. A method was developed for the extractive atomic absorption determination of cadmium in river water in which a preliminary 200-fold concentration was carried out. The cadmium detection limit was 8 x 10/sup -5/ ..mu..g/ml.