Simple Experiment Assisting Students with Identification of Spectral Interference and Selection Emission Lines for ICP-OES Analysis Using Soil Samples
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Letitia Pillay [1]
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[1] University of the Witwatersrand
University of the Witwatersrand
City of Johannesburg, Sudáfrica
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- Localización: Journal of chemical education, ISSN 0021-9584, Vol. 97, Nº 5, 2020, págs. 1460-1464
- Idioma: inglés
- Texto completo no disponible (Saber más ...)
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Resumen
Inductively coupled plasma optical emission spectroscopy (ICP-OES) is one of the most commonly used analytical techniques for the measurement of metals in environmental matrices. However, one of the drawbacks of ICP-OES is interference, viz., spectral and nonspectral (due to transport effects) interference. In this simple laboratory experiment, spectral interference during ICP-OES analysis of soil samples was investigated. The role of Fe as an interferent was highlighted upon consideration of the analysis of Co. Students digested serpentine soil samples with acid and quantified the Co using several different emission lines. Since Fe is present at levels several orders of magnitude higher than that of Co, spectral interference occurs at 236.380 nm and at 238.892 nm for the analysis of Co. Using the data and spectral emission plots, students selected the appropriate wavelength for quantification and identified specific interference sources. The learning goals include preparing samples successfully , understanding the criteria to select wavelengths for ICP-OES analysis, and the calculating the metal concentration. The experiment is suitable for senior undergraduate and early postgraduate students in analytical and environmental chemistry courses.
