Flame atomic absorption spectrometric determination of cadmium, cobalt, copper, lead and nickel in chemical grade potassium salts after an enrichmentand separation procedure

A simple and sensitive separation and preconcentration technique for the de termination of trace amounts of cadmium, cobalt, copper, nickel and lead in chemical grade potassium salts is described. Analytes were complexed with 1-nitroso-2-naphthol at pH 6. Following solid-phase extraction on Amberlite XAD-4 resin, metals were determined by flame atomic absorption spectrometr y. The recoveries of metal ions were greater than 95 %. The detection limit s were between 16 ng/L (Cd) and 59 ng/L (Ni). The relative standard deviati on (RSD) of the determinations varied from 1 to 7 %.