Abstract
In the determination of mercury by atomic absorption Spectrometory, the high sensitivity is obtained by the addition of reducing agents.But the decrease of absorbance is observed on standing.To eliminate this standing effects, Y-type reaction tube was used.The process is that mercury solution and reducing agent solution are aspirated separately and the two solutions are mixed in a Y-type reaction tube.Furthermore, the effect of reducing agents, acids, pH and diverse ions were investigated.Among reducing agents, tin (II) chloride was found to be the best agent and absorbance could be raised to about fifteen-folds.Detection limit of this method was 0.02ppm of mercury and the coefficient of variation was 1.1% at 10ppm Hg level. When the ammonium nitrate was contained, the absorbance of mercury was constant at a pH of 1-10.
One ppm of I- and 200ppm of SCN- affected, but interference of other ions is negligible. The analytical results of mercury in numerical indicator tube by this method was satisfactorily in agreement with dithizone method.
