Rapid assessment of the latent hazard posed by dissolved mercaptans within aqueous effluent.
The presence of mercaptans (RSH) can usually be detected by their inherent noxious odour but there is a need to quantify the concentration within effluent and hence allow an assessment of the latent hazard to be made prior to disposal. The versatility of using naphthoquinone as a rapid derivatising agent through which to trap such species has been evaluated. The quinone moiety provides a label that can be quantified using colorimetric, electrochemical and chromatographic means and offers a significant advantage over conventional thiol labelling agents. The analytical characteristics of each approach have been investigated and the selectivity, sensitivity and applicability of the reaction system critically assessed for a range of model compounds. The naphthoquinone system has a detection limit in the low micromolar range with little interference from other components common to discharge water with 96% recovery of mercaptopropionate. The reaction to sulfide (HS-) has also been assessed and a disparity in response between the detection methods observed and a possible reaction pathway outlined.
School of Biomedical and Natural Sciences, Nottingham Trent University, Nottingham NG11 8NS, UK.
Maria Marti
MM
Villalba
Verity J
VJ
Litchfield
Robert B
RB
Smith
Anthony M
AM
Franklin
Nathan S
NS
Lawrence
James
J
Davis
D009285:Naphthoquinones / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D009285:Naphthoquinones; D013438:Sulfhydryl Compounds; D014874:Water Pollutants, Chemical