1975 Volume 1975 Issue 5 Pages 836-841
An atomic absorption spectrophotometric method by using a carbon-tube flameless atomizer was proposed for the determination of trace amounts of cadmium, lead and copper. In this method, the use of dithizone-carbon tetrachloride extraction system was recommended for a pretreatment to remove interfering materials such as large amounts of alkali and alkaline earth metal salts. The extraction system has several features as follows. ( 1 ) Dithizone and the dithizonates are fairly stable. ( 2 ) Excess and deficiency of the reagent can be easily found from the coloration of organic phase. ( 3 ) Cadmium (≤0.04ug), lead (≤0.8ug) and copper (≤0.8ug) are quantitatively and simultaneously extracted in a pH range 5-10.5, even by using a large aqueous/organic phase volume ratio (Vw/ Vo) such as 50. ( 4 ) Consistent calibration curves are obtained for both fresh and sea waters.
The sensitivities for 1 % absorption of the method with the Vw/Vo, of 10, were 0.004 ppb for cadmium and 0.09 ppb for lead and copper. The coefficient of variations (10 replicate samples) was about 3% in each case. Most diverse ions which interfered with the determinations of cadmium, lead and copper in the case of direct injection of aqueous samples, gave no effect even when present in 1000-fold amounts, but cations such as zinc, copper and nickel at several tens times, interfered with the determination of lead.
The method was applied to the analysis of river and sea waters, and soil extracts.
This article cannot obtain the latest cited-by information.
