Royal Society of Chemistry, Analytical Methods, 6(7), p. 2687-2692
DOI: 10.1039/c4ay02952f
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H2S is extremely malodorous, has a low odor threshold, and is a toxic and corrosive gas. These properties make localized emissions of hydrogen sulfide an air pollution issue. Despite a relatively large number of papers dedicated to developing analytical methods to determine gaseous H2S, it remains an analytical problem under some conditions. There are factors contributing to this fact, such as potential interferences of other compounds present in the air sample, gas interaction with surfaces, resulting in adsorption or oxidation reactions and a lack of sulfur-selective sensors adequate for field use. In this paper, we describe a luminescent cellulose filter-based sensor for gaseous H2S determination. The cellulose filter is impregnated with a palladium complex, containing a ligand with fluorescent properties. The measurements are made directly on the cellulose filter, not requiring an extraction step. The palladium complex - bis 2-aminobenzoic palladium (II) - impregnated on the surface of cellulose filter paper reacts with gaseous H2S. The reaction results in the release of the fluorescent ligand, increasing the fluorescence intensity of the filter surface observed at 410 nm when excited at 338 nm. The linear calibration curve covers the range of 8 – 110 ppb with a limit of detection (LOD) at 2 ppb. The sampling time is approximately 15 min for this range of H2S; however, longer sampling may decrease the detection limit. The factors affecting the collection characteristics, such as sampling flow, media moisture, cellulose filter paper type and amount of humectant (ethylene glycol) in the impregnating solution amount, were optimized