ICP-AES Determination of Copper Mercury and Lead in Tap Water

ICP-AES was applied to the determination of trace amout of Cu, Hg and Pb in tap water. The acidity of water sample was adjusted with HNO3 (2+98) solution, and n-propyl alcohol was added to enhance intensity of spectral lines of the 3 elements determined and to raise the signal to background ratio of the spectra. High-frequency power of 1 100 W and atomizing pressure of 230 kPa were taken in the analysis. Under the optimized conditions, detection limits (3s) of the method found were 2.32 μg·L-1 for Cu, 8.34 μg·L-1 for Hg and 5.16 μg·L-1 for Pb. The proposed method was used in the analysis of samples of tap water, and values of RSD′s (n=5) of Cu, Hg and Pb found were 3.3%, 8.0% and 9.3% respectively.