抄録
A sensitive and selective method for the determination of trace amounts of cobalt(II) is described. The method is based on the combined use of 1-(2-pyridylazo)-2-naphthol (PAN) and 2-(5-bromo-2-pyridylazo)-5-[N-propyl-N-(3-sulfo-propyl)amino]phenol (5-Br-PAPS). Cobalt(II) is first extracted on a membrane filter as the cobalt(III)-PAN complex and the complex is decomposed with acid. The cobalt is then extracted on a membrane filter as the cobalt(III)-5-Br-PAPS complex in the presence of dodecylbenzenesulfonate and determined by densitometry. The proposed method has been applied to the determination of cobalt in tap water and beverages.
