Chemical Mechanism and Efficiency of the Sulfur Chemiluminescence Detector

The sulfur chemiluminescence detector (SCD) is a sensitive, highly selective sulfur detection system based on reaction in hydrogen/air combustion followed by extraction and low-pressure chemiluminescence. This report documents investigations into the fundamental chemical processes occurring in the SCD. The conclusion from this work is that ozone reacts with sulfur monoxide (SO) to form electronically excited SO2. A gas-phase titration of the SO formed indicates that approximately four of every 1000 sulfur-containing molecules entering the flame arrive at the reaction cell as SO. This new understanding of the SCD will allow future studies to concentrate on optimization of instrumental performance based on the appropriate chemical mechanism.