Reduced sulfur (sulfide) compounds occur naturally in the environment and can be produced under anaerobic conditions in industrial processes [1]. Sulfide attacks metals and concrete, and causes corrosion on pipe walls [2]. Monitoring of sulfide in water is also required in order to avoid any toxic effects on humans and aquatic organisms [3]. The present research reports a vortex-assisted liquid-liquid microextraction procedure along with UV-Vis spectrohotometric method based on methylene blue formation reaction for selective and sensitive determination of total and dissolved sulfide ion in drinking, surface and saline waters, domestic and industrial wastes. Sulfide reacts with N,N-dimethyl-p-phenylenediamine in the presence of ferric chloride to produce methylene blue, a dye which is extracted into 1,2 dichloroethane organic solvent and measured at the wavelength maximum of 625 nm. The influence of various chemical and microextraction relevant parameters has been investigated and the performance of the method optimized. Under the optimized operating conditions, the proposed method could successfully detect the sulfide in the concentration range of 50 to 500 ng L−1 with a detection limit (3sb/m citerion) of 18 ng L−1. Effects of several potential interferences have also been studied. The method was successfully applied to determine sulfide in leachates and various types of water samples.

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