Determination of Trace Elements in Different Powdered Samples by Atomic Emission Spectrometry with Spectral Excitation in a Two-Jet Arc Plasmatron

摘要

The effects of operating parameters and easily ionized additives on the analytical signal in the region before the confluence of plasmatron jets were studied. It was shown that the effective atomic excitation temperature in this region is independent of the concentration of NaCl (0–50%) in the graphite powder. Amethod was proposed for the direct atomic emission determination of trace elements in powdered samples. In this method, multielement analysis of various samples, such as graphite concentrates of trace impurities, soils, bottom sediments, plants, and humic acids can be performed under unified conditions using a unified set of reference samples without sample mineralization and dissolution. At the stage of sample preparation, a finely divided sample is mixed with a spectroscopic buffer (graphite powder doped with NaCl). The detection limits for several dozen elements in their direct determination varied from 10~(-6) to 10~(-4) wt% at a relative standard deviation (RSD) of no worse than 15%.