Determination of Co, Ni, Cr and Cu in galena and sphaleriteudby zeeman electrothermal atomic absorption spectrometry

摘要

Methods for the determination of Co, Ni, Cu and Cr in galena (PbS) and sphalerite (ZnS) by Zeeman electrothermal atomic absorption spectrometry have been proposed. Interferences were investigated by measuring the absorbance of Co, Ni, Cu and Cr in series of samples with varying mass ratios of investigated elements and potential interfering elements (Pb and Zn). Sincc, it was found that there is no interference in the determined mass ratios of the matrix and the investigated elements, Co, Ni, Cu and Cr were directly analyzed from the solution obtained by dissolution of galena in mineral acids (HCI and HN03). In the case of sphalerite Co, Ni and Cr were di­rectly analyzed from the solution. Results show that the interfering clement (Zn) tend to decrease the absorbance of copper at high concentrations. The procedurc was verified by the method of standard additions and the results were compared with those obtained by inductively coupled plasma-atomic emission spectrometry (ICP-AES). Investigated minerals originate from different lead and zinc mines from the Republic of Macedonia. ud