Determination of trace amounts of sulfur in steel by electrothermal vaporization—inductively coupled plasma mass spectrometry

Abstract

A method is described for the determination of trace amounts of S in steel by ETV–ICP-MS. The effect of Fe, Cu, Al, Si, V, Co, Ni, Cr, Mo, Ti, Mn and W on S signals and the use of KOH as a chemical modifier were studied. Most concomitant elements affected the intensity and shape of the S ETV–ICP-MS signal. The addition of KOH as a chemical modifier only partially eliminated these interference effects. The use of isotope dilution calibration and the removal of Fe by solvent extraction with 4-methylpentan-2-one were used to compensate for interference effects. A precision of ± 0.2 µg g–1 at an S concentration of 2 µg g–1 was achieved. The limit of detection for S in steel was 0.05 µg g–1.