Spectrophotometric determination of trace amounts of sulfide ion based on its catalytic reduction reaction with Methylene Blue in the presence of Te(IV)

A simple, rapid and sensitive catalytic kinetic method was used for the determination of trace amounts of sulfide based on its catalytic reduction of Methylene Blue(MB) in the presence of Te(IV). The reaction was monitored spectrophotometrically by measuring the change in absorbance of the reaction mixture at 663 nm. The fixed time method was used for the first 1.5 minute from initiation of reaction. Under the optimum conditions, in the concentration range of 0.05-2 mu g/ml of sulfide ion, a linear curve (r = 0.998) was obtained. The detection limit is 0.025 mu g/ml. The relative standard deviation of ten replicate measurements is 2.1% for a 1 mu g/ml solution of sulfide. The proposed method was applied for the determination of sulfide in spring and waste water.