Quantification of Hydrogen Sulfide and Methanethiol and the Study of Their Scavenging by Biocides of the Isothiazolone Family

Abstract

A sensitive analytical method for the quantification of malodourous hydrogen sulfide (H2S) and methanethiol (CH3SH) was developed and validated. The method consisted of solid‐phase microextraction with concomitant in‐fibre derivatisation of the mercaptan using N‐ethylmaleimide. The adducts were analysed by GC–MS using a triple quadrupole in the selected reaction monitoring mode. The limits of detection of solutions of H2S and CH3SH in water were 100 and 10 ng L−1, respectively, below their odour‐perception thresholds. The analytical method was used to show the scavenging effect of 1,2‐benzisothiazol‐3(2H)‐one (Proxel) and 2‐methyl‐4‐isothiazolinone. The mechanism by which H2S and CH3SH are trapped with Proxel was studied by ultraperformance liquid chromatography (UPLC)‐MS.

Identification of Hydrogen Disulfanes and Hydrogen Trisulfanes in H2S Bottle, in Flint, and in Dry Mineral White Wine

“…The GC-MS analysis of the contaminated gas cylinder displayed two major signals with a mass of 284, corresponding to the molecular formula C 12 H 16 N 2 O 4 S with m / z 127 (C 6 H 9 NO 2 ), typical for the NEM moiety. These two signals were assigned to the NEM-S-NEM diastereoisomers. ,, Additional compounds with a fragment corresponding to m / z 127 were detected with masses corresponding to 173, 187, 205, 219, and 316 (MS in the Supporting Information). The possible chemical structures should be limited to compounds that are closely related to H 2 S. From the masses and the fragmentation patterns of NEM derivatives, M + 173 was attributed to methylmercaptan, M + 187 to ethylmercaptan, and M + 205 and 219 to their disulfides; M + 316 could well be attributed to NEM-S-S-NEM.…”

Characterization of odour‐active compounds in Timur (Zanthoxylum armatum DC.) fruits from Nepal

“…In fibre derivatization using N‐phenylmaleimide or N‐ethylmaleimide reagents was tested according to the protocols described by Wang et al and Frerot et al . , respectively. The same reagents and SPME conditions were used.…”

“…Preconcentration of thiols on an SPE cartridge containing phydroxymercurybenzoate was also tested according to the protocol reported by Mateo-Vivaracho et al 32 2.9.2 | In fibre SPME derivatization by maleimide derivates In fibre derivatization using N-phenylmaleimide or N-ethylmaleimide reagents was tested according to the protocols described by Wang et al 33 and Frerot et al 46 , respectively. The same reagents and SPME conditions were used.…”

50 Years of Mass Spectrometry at Firmenich: A Continuing Love Story

“…Recently, Frérot et al [19] developed a GC-MS-MS method for the quantification of the malodorous compounds hydrogen sulfide and methyl mercaptan. They used a solid-phase microextraction method with in-fiber derivatization.…”