Plasma atomic emission spectrometric determination of sulfur in the vacuum ultraviolet region of the spectrum

A dc discharge plasma source has been utilized for the determination of sulfur in solutions using optical atomic emission spectroscopy. The sulfur resonance lines which occur at 180.7, 182.0, and 182.6 nm were used in this work. A simple argon purge system was developed to reduce light absorption by oxygen. This excitation source, coupled with the purge system, appropriate optics, and detection equipment, enabled the determination of total sulfur in aqueous solutions with the same sensitivity for different sulfur species. A detection limit of 0.5 ppM and a linear dynamic range of 2000 ppM sulfur were attained. Several potential chemical and spectral interferences were investigated. The instrumentation was also used to determine sulfur in organic solvents and to determine Hg, Se, As, I, and P in aqueous solutions