Packed-Column Supercritical Fluid Chromatography with Chemiluminescent Nitrogen Detection at High Carbon Dioxide Flow Rates

摘要

The use of chemiluminescence nitrogen detection (CLND) coupled with packed-column supercritical fluid chromatography is investigated. The pyrolysis tube design, position of the restrictor, and reaction chamber pressure are shown to affect the response of the detector. By modifying the pyrolysis chamber and controlling the pressure at the reaction chamber, the response of the detector remains constant when different concentrations of methanol modifier are used. This detector design also tolerates high flow rates of decompressed CO↓(2). As a result, no post-column split is required and the total column effluent is delivered to the CLND. Sensitive detection (limit of detection = 1 ng nitrogen) is achieved at the high flow rates of decompressed CO↓(1) with 8% methanol-modified C0↓(2).