Improved measurement of sulfur and nitrogen compounds in refinery liquids using gas chromatography atomic emission detection

The measurement of sulfur and nitrogen compounds in refinery liquids is an important analysis for the petroleum industry. Gas chromatography with atomic emission detection (GC-AED) provides a useful means of selectively detecting these compounds. This article presents a GC-AED method optimized for the analysis of sulfur and nitrogen compounds in gasoline through diesel-range materials. By optimizing such parameters as element wavelength, detector gas flow rates, and chromatographic conditions, the selectivity in the presence of hydrocarbons is increased 10-fold for sulfur and by more than 100-fold for nitrogen. These gains in selectivity result in the ability to measure sulfur and nitrogen at low parts-per-million levels.