National Oceanic and
Atmospheric Administration
United States Department of Commerce


 

FY 1988

Electron capture sulfur detector: Reduced sulfur species detection at the femtomole level

Johnson, J.E., and J.E. Lovelock

Anal. Chem., 60(8), 812–816, doi: 10.1021/ac00159a016 (1988)


We have developed a new technique to detect reduced sulfur compounds by fluorination with F2 (at 200 ppm) on a heated Ag catalyst after GC separation. The excess F2 is removed by conversion to HF by reaction with H2 on a heated Pd catalyst. The fluorination product, presumably SF6, is then detected in an electron capture detector (ECD). The Pd catalyst also destroys the response from halocarbons making the system sulfur specific. This ECD sulfur detector has a calculated minimum detectable level (MDL) for H2S, OCS, CH3SH, DMS, and CS2 of less than 2 fmol/s for each compound, 2 orders of magnitude lower than the best FPD systems. The ratio of the detected molar response of each of these sulfur compounds to the molar response of SF6 ranges from 2% to 20% and increases with increasing AgF2 temperature.




Feature Publications | Outstanding Scientific Publications

Contact Sandra Bigley |