Comparative application of sulfur chemiluminescence detection in gas and supercritical fluid chromatography

Sulfur chemiluminescence detection (SCD) for the determination of sulfur-containing compounds in gas chromatography (GC) and supercritical fluid chromatography (SFC) is described. The detector is based on the chemiluminescence reaction of ozone with sulfur monoxide which is produced in an H2/O2 reducing flame from sulfur-containing analytes. High selectivity over nonsulfur-containing species has been achieved for a number of mercaptans and sulfur-containing polycyclic aromatic hydrocarbons. Minimum detectable quantities of 23 and 26 pg S (S/N=3) for dibenzothiophene and benzo[b]naphtho[1,2-d]thiophene, respectively, have been obtained using the SFC/SCD system. It was found that connecting a buffer volume flask to the vent of the vacuum pump that draws the effluents and ozone gas into the chemiluminescence reaction chamber, increases the sensitivity of the SCD.