Comparison of different procedures for the analysis of high-purity potassium nitrate by inductively coupled plasma atomic emission spectrometry

Abstract

Different methods for the preconcentration (precipitation of the matrix, solvent extraction and ion exchange) of Cd, Co, Cr, Cu, Fe, Mn, Ni, V and Zn in high-purity potassium nitrate were optimized and evaluated on the basis of elemental spike recovery and reproducibility, as determined by inductively coupled plasma (ICP) atomic emission spectrometry. Samples were analysed by the procedures established and the results were compared with those of a direct semi-quantitative ICP mass spectrometric method and an electrothermal atomic absorption spectrometric determination of Fe after extraction with HCl–isobutyl methyl ketone. Recommendations about the methods under consideration, suitable for the determined elements, are proposed.