Flame photometric detector, sulfur dioxide

The chemiluminescent reaction with chlorine dioxide provides a highly sensitive and highly selective method for only two sulfur compounds, hydrogen sulfide and methane thiol [81]. As in the flame photometric detector (FPD), discussed below, atomic sulfur emission, S2(B3S -> ) is monitored in the wave-... 

Sulfur Dioxide. Both flame photometric and pulsed fluorescence methods have been applied to the continuous measurement of S02 from aircraft. In the flame photometric detector (FPD), sulfur compounds are reduced in a hydrogen-rich flame to the S2 dimer. The emission resulting from the transition of the thermally excited dimer to its ground state at 394 nm is measured by using a narrow band-pass filter and a photomultiplier tube. 

Sulfur dioxide may be determined after removing it from foods by distillation, and titration with sodium hydroxide in the presence of methyl red. GC headspace analysis with a flame photometric detector has also been used for the quantification of this food additive. 

Sulfur Chemiluminescence Detector. Another sulfur selective detector based on photometric sensing of a chemiluminescent reaction has become commercially available (Sievers Research, Inc., Boulder, CO). Similar to the FPD, the detection scheme of the SCD incorporates combustion of the GC column effluent in a hydrogen rich flame. However, the sulfur species detected is an excited state of sulfur dioxide (SO2 ), not... 

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