Speciation of sulfur-containing compounds in diesel by comprehensive two-dimensional gas chromatography.

Sulfur-containing compounds in diesel have been speciated by comprehensive two-dimensional gas chromatography (GCxGC) with a sulfur chemiluminescence detector (SCD). The advantages of GCxGC technique are higher resolution and greater sensitivity. GCxGC-SCD can achieve the class separation of sulfur-containing compounds with an appropriate separation column combination. The major classes of sulfur-containing compounds in diesel are benzothiophenes and dibenzothiophenes. Relative concentration of each class as well as each carbon number family can be quantitated by the summation of the integrated areas corresponding to the individual group(s) in the GCxGC space. In practical applications, GCxGC-SCD can be used to characterize different diesels and to reflect desulfurization process efficiency. In this study, GCxGC-SCD has demonstrated its value in speciation of sulfur-containing compounds classes, which is difficult to accomplish by any other single technique.