A method for the atomic absorption spectroscopic determination of cadmium extracted with the APDC (ammonium pyrrolidinedithiocarbamate)-MIBA (methyl isobutyl ketone) is described. We examined various condition of the extraction of cadmium and of the atomic absorption analysis.
Cadmium was efficiently extracted from the aqueous solution adjusted to the pH 3.5-10.3 range and to the salt concentration over 2.5M with saturated ammonium sulfate solution. Under these conditions, cadmium in 25ml of the aqueous solution was completely extracted with 10ml of MIBK by a single extraction. When the aqueous solution increased to 50ml, the extractability was still 97 per cent.
The presence of a large amount of zinc, lead and mangane decreased the absorbance of cadmium owing to the poor solubililties of APDC-chelates in MIBK.