Pulsed discharge emission detector: an element-selective detector for gas chromatography

Area of Science:

• Analytical Chemistry
• Spectroscopy

Background:

• Direct observation of vacuum UV atomic emissions from halogens (Cl, Br, I) and sulfur (S) is challenging.
• Existing detection methods may lack element specificity or sensitivity for these elements.

Purpose of the Study:

• To develop and evaluate an element-specific pulsed discharge emission detector (PDED) for detecting vacuum UV atomic emissions.
• To assess the sensitivity and qualitative identification capabilities of the PDED when coupled with a vacuum UV monochromator.
• To compare the performance of the PDED with a helium pulsed discharge photoionization detector (He-PDPID).

Main Methods:

• Coupling an element-specific pulsed discharge emission detector (PDED) directly with a vacuum UV monochromator.
• Observing vacuum UV atomic emissions from Cl, Br, I, and S.
• Simultaneous operation of the PDED and a helium pulsed discharge photoionization detector (He-PDPID).
• Analyzing chromatograms for peak shape and detector response ratios.

Main Results:

• The PDED successfully observed vacuum UV atomic emissions from Cl, Br, I, and S.
• Observed sensitivities for these elements were in the mid to high picogram per second (pg/s) range.
• Chromatograms from PDED and He-PDPID showed similar peak shapes, indicating no peak tailing.
• The ratio of PDED/He-PDPID detector responses proved useful for qualitative identification of halogen- and sulfur-containing compounds.

Conclusions:

• The developed PDED is a sensitive and element-specific detector for vacuum UV atomic emissions.
• The PDED offers good chromatographic performance without peak tailing.
• The combined use of PDED and He-PDPID enables qualitative identification of target compounds based on response ratios.