Cadmium(II)-Exchanged Zeolite as a Solid Sorbent for the Preconcentration and Determination of Atmospheric Hydrogen Sulfide II: Spectroscopic Techniques

Instrumental techniques are compared for usage in the determination of atmospheric H 2 S which has been preconcentrated on Cd(II)-exchanged zeolite. The study covers the range of 0.01 to 100 μg of immobilized sulfide. For high concentrations (2–100 μg), combustion analysis followed by nondispersive IR is the simplest and most precise technique, and results with the use of this method are accurate to ±3% relative. In the range of 0.25–40 μg, the sulfide, after conversion to methylene blue, may be determined by conventional spectrophotometry, with a relative precision of ±13%. For the lowest concentration range investigated (0.01–2.0 μg), photoacoustic spectroscopy gave the only quantitative results after the H 2 S was converted to methylene blue.