FY 1988

The 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 (1988)

We have developed a new technique to detect reduced sulfur compounds by fluorination with F (at 200 ppm) on a heated Ag catalyst after GC separation. The excess F is removed by conversion to HF by reaction with H on a heated Pd catalyst. The fluorination product, presumably SF, 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 HS, OCS, CHSH, DMS, and CS 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 SF ranges from 2% to 20% and increases with increasing AgF temperature.