Determination of Lead in Laterice Nickel Ore by Flame Atomic Absorption Spectrometry

Laterice nickel ore was digested with mixed acids of HCl and HNO₃ mixed acids. HF was used to remove silicon, and residual HF was volatilized by using HClO₄. Lead content in the HNO₃ solution was determined by Flame Atomic Absorption Spectrometry. The different acid digestion systems and interferences of coexistent elements are presented in this paper. The results showed that the samples were completely dissolved by HCl-HNO₃-HF-HClO₄ mixed acids. The Pb level content was not influenced by HNO₃ when its acidity was below 5% (V/V). The coexistent elements of Fe (1000 μg/mL), Ni (60 μg/mL), Cu (10 μg/mL), Ca (50 μg/mL), Mn (20 μg/mL), Cr (10 μg/mL), Co (10 μg/mL) and Zn (10 μg/mL) did not interfere with the Pb result (1 μg/mL). The detection limit was 0.044 μg/mL at selected working conditions. The accuracy of the Pb content was verified by adding a standard solution to the laterice nickel ore. The recoveries ranged from 97% to 106%, and the results of this method were in agreement with inductively coupled plasma atomic emission spectrometry. The proposed method is a useful technique with good repeatability and accuracy.