Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 1/28/2003
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: Traditional gas chromatographic methods for the determination of hydrogen and methane at the ppmv level require two separations with different detectors; a Thermal Conductivity Detector (TCD) for hydrogen and a Flame Ionization Detector (FID) for methane. A Pulsed Discharge Helium Ionization Detector (PDHID) can be used for the simultaneous determination of hydrogen and methane in the breath of human subjects. The limit of quantification for this method was at least an order of magnitude lower than the FID/TCD method (300 ppbv vs. 6 ppmv for both hydrogen and methane as determined by calibration curves). However, the non-selective nature of the PDHID requires an increase in the separation time from 90 to 300 seconds. Because the PDHID has lower limits of quantification than the TCD it is a useful tool for monitoring industrial processes. Hydrogen sulfide produced from the microbiological reduction of sulfur dioxide in a bench-scale simulated flue-gas bioreactor can be quantified in less than three minutes at concentrations greater than 1 ppmv. Because the PDHID is universal, the reactor can be monitored for side products such as dimethylsulfide, dimethyldisulfide and carbonyl sulfide. The expanded linear range of the PHID allows for the simultaneous detection of multiple side products that vary in concentration by more than two orders of magnitude.