A novel reagent for separation, trace determination of mercury by spectrophotometry, cold vapor atomic absorption spectroscopy (AAS), and membrane separation

A simple, selective separation and trace determination of mercury is described. The mercury is extracted quantitatively at pH 9.0 with 7‐hydroxy‐4‐methyl coumarin hydroxamic acid (HMCHA) with dichloromethane, and has the maximum absorbance at 480 nm with molar absorptivity (ɛ) with Beer's law between 0.1 and 20 ppm. The Hg–HMCHA extracts a yellowish brown color. The mercury is determined by cold vapor atomic absorption, which increases the sensitivity 20 times. The mercury is extracted in the presence of several ions without any interference quantitatively. The method has been applied to the determination of mercury in standard and environmental samples.