SULFUR-SELECTIVE CHEMILUMINESCENCE DETECTION WITH PACKED-COLUMN SUPERCRITICAL-FLUID CHROMATOGRAPHY

A new generation sulfur chemiluminescence detection (SCLD) system was interfaced and tested for supercritical fluid chromatography (SFC) wit h packed columns using 100% SF-CO2 and methanol modified CO2 as the mo bile phase. The detection chemistry for the SCLD is based on ozone-ind uced chemiluminescence following a two-step combustion process of cons ecutive oxidation and reduction of sulfur-containing compounds. A seve n-day evaluation study showed excellent sensitivity, selectivity and l inearity, as well as day-to-day repeatability. The minimum detectable quantity was determined to be 3 pg sulfur (0.2 pg S/s) at the detector . Equimolar response of SCLD to sulfur compounds with different bondin g environments was also observed. Unique applications and capabilities of the SFC-SCLD system for sulfur speciation and detection are presen ted for a petroleum product, thermally labile pesticides and herbicide s which are difficult or impossible to analyze by GC techniques, (C) 1 997 Elsevier Science B.V.